AltME groups: search

digit: charset "0123456789"
number: [1 3 digit]
s: "testse193.194.70.123 1080iiyyyuiyiy  234.221.23.5:3380"

parse s [some [start: digit 3 [number "."] number opt [#":" 1 5 digit] 
end: (print copy/part start end) | skip]]
;193.194.70.123
;234.221.23.5:3380
;== true

ips: copy []

parse/all s [some [(port: none) start: digit 3 [number "."] number 
opt [#":" port: 1 5 digit] end: (append ips reduce [load copy/part 
start any [all [port back port] end] if port [load copy/part port 
end]]) | skip]]

parse s [some [start:   3 [number "."]   number opt #":" 1 5 digit 
 end: (append ips parse copy/part start end ":") | skip]
]

parse s [some [start:   3 [number "."]   number opt #":" 1 5 digit 
 end: (append ips load  replace  copy/part start end ":"
 " " ) | skip]]

parse/all s [some [start: digit 3 [number "."] number x: 1 10 char 
y: 1 5 digit   end: ( probe reduce [ copy/part start x  copy/part 
y end]) | skip ]]

Here are some minimum additonal parse operations, and some workarounds 
that could be used to replace them until they are implemented.

fail ==> [end skip]
check (code) ==> (tmp1: unless (code) [fail]) tmp1
remove rule ==> tmp1: rule tmp2: :tmp1 (remove/part :tmp1 :tmp2)

replace rule (code) ==> tmp1: rule tmp2: :tmp1 (tmp1: change/part 
:tmp1 (code) :tmp2) :tmp1

replace-only rule (code) ==> tmp1: rule tmp2: :tmp1 (tmp1: change/part/only 
:tmp1 (code) :tmp2) :tmp1

into-string rule ==> set tmp1 string! (tmp1: unless parse tmp1 rule 
[fail]) tmp1


Note that if parse operations are changed to take refinements or 
if these are being done as rewrite rules, replace-only and into-string 
could be expressed as remove/only and into/string. This would be 
slower in a native implementation, but about the same in rewrite 
rules. It would look more REBOL-like if that matters to you.


A rewrite engine for these workarounds will need temporaries for 
their implementation. The caller would need to provide a block of 
their own temporaries, and would not be able to reuse them in their 
code. The rewriter will need to count temporaries and complain if 
the caller doesn't provide enough. As with all parse rules, these 
temporaries will not be recursion-safe. Directly nested rules should 
be fine as long as there are enough temporaries provided.

switch2: func [

    "Selects a choice and evaluates the first block that follows it."
    [throw]
    value "Value to search for."
    cases [block!] "Block of cases to search."
    /default case [block!] "Default case if no others are found."
    /local rule
][
	rule: [
		1 1 () ; <-- value
		to block! set value block! (return do value) 
		to end
		| skip to () ; <-- type? value
	]
	rule/3: value
	change back tail rule type? value
	any [
		parse cases [some rule]
		do case
	]
]

;test
repeat n 10 [
	print [
		n

  switch2/default n [2 4 6 ['even] 1 3 5 ['odd]] [mold "--default--"]
	]
]
switch2 1 []
switch2/default 1 [] ["--default--"]

switch2: func [

    "Selects a choice and evaluates the first block that follows it."
    [throw]
    value "Value to search for."
    cases [block!] "Block of cases to search."
    /default case [block!] "Default case if no others are found."
    /local rule
][
	rule: [
		1 1 () ; <-- value
		to block! set case block! ; <- re-use the 'case variable
		to end
		| skip to () ; <-- type? value
	]
	rule/3: value
	change back tail rule type? value
	parse cases [some rule]
	do case
]

{switch2: func [

    "Selects a choice and evaluates the first block that follows it. 
    This occurs for every matching value and following block found."
    [throw]
    value "Value to search for."
    cases [block!] "Block of cases to search."
    /default case [block!] "Default case if no others are found."
    /local rule
][
	rule: [
		1 1 () ; <-- value

  to block! set case block! (case: do case) ; <- re-use the 'case variable, 
  twice...
		| [skip to ()] ; <-- type? value
		| skip
	]
	rule/3: value
	rule/11/3: type? value
	any [
		all [
			parse cases [some rule]
			case
		]
		do case
	]
]}

;test
repeat n 10 [
	print [
		n

  switch2/default n [2 4 6 ['even] 1 3 5 ['odd]] [mold "--default--"]
	]
]
switch2 1 []
switch2/default 1 [] [probe "--default, ok--"]
switch2 1 [1 [probe "ok"]]
switch2 2 [1 [probe "bad"]]
switch2 1 [1 2 [probe "ok"]]
switch2 2 [1 2 [probe "ok"]]
switch2 3 [1 2 [probe "bad"]]

; multiple action blocks
switch2 1 [1 2 [probe "ok"] 1 3 4 [probe "ok#2"]] ; <-- 
switch2 2 [1 2 [probe "ok"] 1 3 4 [probe "bad"]]
switch2 3 [1 2 [probe "bad"] 1 3 4 [probe "ok"]]
switch2 4 [1 2 [probe "bad"] 1 3 4 [probe "ok"]]
switch2 5 [1 2 [probe "bad"] 1 3 4 [probe "bad"]]


switch2/default 5 [1 2 [probe "bad"] 1 3 4 [probe "bad"]] [probe 
"--default, ok--"]

context [
	stack: make block! 10
	foreign-rules: make block! 10
	out: end: value: pos: none
	push: func [type][
		stack: change/only stack out 
		out: make type 1 
	]
	pop:  to-paren [
		stack: back stack 
		out: append/only stack/1 out
	]
	set-&: [end: (misc/&: to string! copy/part pos end)]
	misc: context [
		&: none
		keep: func [&][append out &]
	]
	blanks: charset " ^-^M"
	rules: [
		  some [blanks | #"^/" (new-line out true)]	  
		| pos: foreign-rules
		| [#"]" | #")"] (print "missing [ or (" return stack/1)
		| #"[" (push block!) any [#"]" pop break | rules]
		| #"(" (push paren!) any [#")" pop break | rules]

  | (set [value pos] transcode/next/error pos append out value) :pos
	]
	
	set 'load-foreign func [
		text [string!] foreign [block!]
	][
		out: make block! 10
		stack: change/only clear head stack out
		clear foreign-rules
		foreach [rule code] foreign [

   append foreign-rules compose [(rule) set-& (to-paren bind code misc) 
   |]
		]
		append foreign-rules  [end skip]
		parse/all to-binary text [any rules]
		bind out 'system
		either 1 = length? out [first out][out]
	]
]

form-decimal: function [num][tmp main rest sign base][

     either found? find tmp: to-string num "E" [

              parse tmp [
                 copy main to "."
                 skip
                 copy rest to "E"
                 skip
                 mark: (sign: copy/part mark 1)
                 skip
                 copy base to end
               ]


        either sign = "-" [

                tmp: "0."

                loop ((to-integer base) - 1) [insert tail tmp "0"]
                insert tail tmp rest
        ][
                tmp: copy ""

                insert tail tmp join main rest

                loop ((to-integer base) - (length? rest)) [insert tail tmp "0"]  
                    
                           
        ] 
     
      tmp                 

     ][num] 

]

form-decimal: func [num /local tmp main rest sign base][

     either found? find tmp: to-string num "E" [

              parse tmp [
                 [copy main to "." 
                  skip
                  copy rest to "E"
                  |
                  copy rest to "E"
                  (main: copy "")  
                  ]
             
                 skip
                 mark: (sign: copy/part mark 1)
                 skip
                 copy base to end
               ]


        either sign = "-" [

                tmp: copy "0."

                loop ((to-integer base) - 1) [insert tail tmp "0"]
                insert tail tmp rest
        ][
                tmp: copy ""

                insert tail tmp join main rest

                loop ((to-integer base) - (length? rest)) [insert tail tmp "0"]  
                    
                           
        ] 
     
      tmp                 

     ][num] 

]

(Back to slicing briefly) REBOL already has functionality equivalent 
to slicing as copy-of-subsection, so this would be better represented 
as a very simple mezzanine function that does the work. If you mean 
slicing as reference-to-subsection-in-place, that would be worth 
adding new support for. Something like:

slice!: make object! [start: end: none]

slice: func [[catch] s [series!] /from b [integer!] /to e [integer!] 
/len l [integer!]] [
    b: either from [at :s b] [:s]
    e: case [
        to at :s e
        len skip :b l
        true tail :s
    ]
    if greater? index? :b index? :e [to: :e e: :b b: :to]
    make slice! [start: b end: e]
]

This is IMO inconsistent and should be changed:

>> ? for
USAGE:
    FOR 'word start end bump body

DESCRIPTION:
     Repeats a block over a range of values.
     FOR is a function value.

ARGUMENTS:
     word -- Variable to hold current value (Type: word)

     start -- Starting value (Type: number series money time date char)

     end -- Ending value (Type: number series money time date char)

     bump -- Amount to skip each time (Type: number money time char)
     body -- Block to evaluate (Type: block)

(SPECIAL ATTRIBUTES)
     catch
     throw
>> a: 2.0
== 2.0
>> for test 1 a 1 [print test]
** Script Error: for expected end argument of type: integer
** Near: for test 1 a 1
>> number? a
== true


It should be possible to use decimal! as well. The interpreter should 
implicitly convert it to an integer!

And loading the registry into a REBOL block is not a problem so far. 
I simply READ the registry-dump file as a string, then PARSE the 
long string into block:

parse-reg: func [ file /local str blk ] [
    str: read file
    blk: copy []
    parse str [ 
        to "[HKEY_" 
        some [
            copy txt thru "]" (append blk txt)
            skip

            copy txt [ to "[HKEY_" | to end ] (append blk trim txt)
        ]
    ]
    str: none
    blk
]

f: read/binary %15.jpg

get-len: [header: skip  (len: to integer! as-binary cp/part header 
2) ]
skip-len: [:header (header: skip header len) :header]
parse f [
        #{FFD8}   ; jpeg Header
        [
                #{FFE0}                         ;JFIF header

                        get-len                 ;get length of a header (2 octets)

                         #{4A46494600}          ;yeah it's a JFIF (confirmation)
                        skip-len
                        some [
                                #{FF}

                                        #{C0}           ;good ! i found the length properties

                                        (print ["height" to integer! as-binary cp/part at header 6 2])

                                        (print ["width" to integer! as-binary cp/part at header 8 2])
                                        break

                                | #{FF}                 ;don't know this header
                                        skip    
                                        get-len 
                                        skip-len
                                | 

                                        [end  skip]     ;error format
                        ]
                        
                        
                | #{FFE1}                       ;EXIF header

                        get-len                 ;get length of a header
                                                ;... to do
                        [end skip]
        ]
        to end
]

REBOL []

parse-async: func [
        file rules
        /local port buffer offset getf seek meta & && result
][
        port: open/seek/binary  file
        buffer: clear #{}
        offset: 1
        getf: func [len][
                offset: offset - length? buffer
                clear buffer 
                append buffer copy/part at port offset len 
                offset: offset + len 
        ]
        seek: [(offset: offset + 1)]
        ..: func [blk] [change/part & compose/deep blk && ]
        parse rules meta: [
                some [

                        &: binary! &&: (.. [buffer: (to-paren reduce ['getf length? &/1]) 
                        (&/1)]) :& 3 skip 
                        | &: 'skip &&: (.. [seek]) :& skip
                        | &: 'get word! integer! &&:

                                (.. [buffer: (to-paren compose/deep [getf (&/3) set [(&/2)] to integer! 
                                as-binary cp buffer]) to end]) :& 4 skip

                        | &: string! &&: (.. [(as-binary &/1)]) :& 
                        | 'end 'skip 
                        | into meta
                        | skip
                ]
        ]
        result: parse/all buffer rules
        close port
        result
 ]
 
if parse-async %15.jpg [
        #{FFD8}   ; jpeg Header
        [
                 #{FFE0}                        ;JFIF header

                        get len 2               ;get data length  for the current header 
                        (2 bytes)

                         "JFIF"                 ;yeah it's a JFIF (confirmation)

                        (len: len - 6) len skip ;skip data (len) times
                        some [

                                 #{FFC0}        ;good ! i found the length properties

                                        2 skip  ; skip length of this header

                                        skip    ; filler ??? always = #{08}
                                        get height 2
                                        get width 2
                                        break   ; finished

                                | #{FF} skip    ;skip this header
                                        get len 2 
                                        (len: len - 2) len skip
                                | 

                                        [end skip]     ;error format
                        ]

                | #{FFE1}                       ;EXIF header

                        get len 2               ;get length of a header
                                                ;... to do
                        [end skip]
        ]
        to end
][
   ?? height
   ?? width
]        
halt

Diss'ing IDE's might alienate some Smalltalk folk.  I cannot imagine 
maintaining an application suite such as I deal with everyday without 
an IDE.  I just wish it was not eclipse ...  Of course only wimps 
used a Disk Operating System and real men code in machine codes only 
... and real pro's dictated their SNOBOL punch cards to lovely assistants 
...  and ANT scripts are for sissies.  Some must have ridiculed Tcl, 
Expect and TK in their day ... but if my IDE can facilitate my efforts 
to systematically (key word there) shrirnk company''s codebase as 
it becomes more reliable with better test coverage then maybe a refactoring 
browser would be a good tool after all.  Even better if it is an 
integrated part of the IDE, as in Dolphin Smalltalk or Squeak Smalltalk 
or Smalltalk/X or Cincom Visual Smalltalk.  Not that I couldn't survive 
on grep and diff's.  But once the codebase is too large for any one 
person to author or maintain on their lonesome, a tool that remebers 
what you did last and where can be a god-send.  If you want to know 
hell without an IDE join an actuarial department working in APL. 
 There you don't even know if they have talent: you just hope most 
of it works as each quarter rolls around and try to survive year-end. 
 But you know they're smart, cuz after all, they're actuaries - and 
look at all that APL code in all those files ... of course a few 
of them look back wistfully at their student days in C with Borland's 
decent IDE.  REBOL [
    File: %vid-usage.r
    Date: 09-Jan-2004   
    Title: "VID Usage"
    Purpose: "VID Usage Tutorial with Runnable Examples"
    Version: 1.2.1
    Author: "Cybarite"
    Edits: RobertS
    Source: {
        Based on %easy-vid.r by Carl Sassenrath.

        Clips from various sites including email that are attributed in the 
        section
        }
    library: [
        level: 'intermediate
        platform: 'all
        type: [tutorial]
        domain: [gui]
        tested-under: [view 1.2.8.3.1 on W2K]
        support: none
        license: none
        see-also: none
    ]
]
 
flash "Fetching image..."
read-thru/to http://www.rebol.com/view/demos/palms.jpg%palms.jpg

read-thru/to http://www.rebol.com/graphics/reb-logo.gif%rebo-logo.gif
read-thru/to http://www.rebol.com/view/bay.jpg%bay.jpg
pic: %palms.jpg
unview

customer: make object! [  ; this sets a default customer object in 
case the user does not push the samples in order
        name: "Rosetta Stone"
        date-of-birth: 14-March-1959        
]

stylize/master [text-note: txt maroon bold]         ; this sets a 
default for users who run the samples out of order
; polished is an image that is embedded in this script file
; so that no outside files need to be loaded.
; This technique is used in many of the REBOL samples

polished: load #{      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}
content: {VID Usage - REBOL Visual Interfaces


===Updates

--01-Apr-2008


* Fixed oddity with last item on stylesheets which was locking up 
some versions of VIEW

---09-Jan-2004

* Fixed slider initialize. 

* Focus section was not parsed out. --- fixed

* Fixed some text errors for the parsing of ===


---07-Jan-2004

* Revived vid-usage.r 

* added more examples from the script library

* manage source as vid-usage.leo an outliner file

---12-August-2001

Added supply examples. See:

!List/Supply

!List With Supplied Data

!Supply List With Scroll

---13-August-2001

!Add Subpanel example ported by Anton

===Caveats

---Work In Progress


This is a work in progress. Whether the progress will continue depends 
on the feedback.

---All Rights Reserved


The work is based on the documentation of REBOL View provided by 
REBOL Technology and its mailing list.

All rights to this documentation remain the property of REBOL Technology.

---Plagiarized Examples


Things are shamelessly plagiarized.  There are many experts on the 
mailing list whose work is included here; most notably the examples 
from the REBOL documentation.

---Approach


The approach that this document uses is to use REBOL/View/VID to 
demonstrate its abilities and give a visual tutorial. To enable this 
some changes have been made to the core %easyvid.r program from Carl 
Sassenrath. A scoll bar was added to the right pane because it was 
just too difficult to constrain the examples to the screen real estate 
that was available.

---Order Order


The order of the items needs some work. The easyvid presentation 
approach today does not allow for the drilling down and expansion 
of an outline tree which is needed for a large amount of documentation.


The preferred approach is to put a multi-level tree for navigation 
purposes and then allow navigation up and down the tree. 


===To Do

* make this a true outline tree

* re-organize it better


* update as requested and as possible by suggestions on AltME's REBOL 
world under group EasyVID

* correct numerous flaws


* better scrolling implementation using the updates that have been 
used in other examples such as Didier's %delete-email.r


* allow clipping to clipboard like AltME does on a row for the source 
examples




===Introduction to VID

With REBOL/View it's easy and quick to create your own user
interfaces. The purpose of this tutorial is to teach you the
basic concepts or REBOL/View interfaces in about 20 minutes.

VID is REBOL's Visual Interface Dialect.  A dialect is an
extension of the REBOL language that makes it easier to express
or describe information, actions, or interfaces.  VID is a
dialect that provides a powerful method of describing user
interfaces.

VID is simple to learn and provides a smooth learning curve from
basic user interfaces to sophisticated distributed computing
applications.


---Creating VID Interfaces

VID interfaces are written in plain text. You can use any text
editor to create and edit your VID script. Save your script
as a text file, and run it with REBOL/View.

!Note: Using a word processor like Word or Wordpad is not
recommended because files are not normally saved as text.
If you use a word processor, be sure to save the output
file as text, not as a document (.doc) file.


Recommendation: Look at TextPad from http://www.textpad.com




===Minimal VID Example

Here is a minimal VID example.  It creates a window that
displays a short text message.  Only one line of code
is required:

    view layout [text "Hello REBOL World!"]

You can type this line at the REBOL console prompt, or save
it in a text file and run it with REBOL.  If you save it
as a file, the script will also need a REBOL header. The
header tells REBOL that the file contains a script. Here
is an example of the script file with a header:

    REBOL [Title: "Example VID Script"]

    view layout [text "VID Example!"]

You can also add buttons and other gadgets to the script. The
example below displays a text, list of files, and a button:

    view layout [
        h2 "File List:"
        text-list data read %.
        button "Great!"
    ]

!Click on the examples above to see how they will appear on your
screen.  Click on their close box to remove them.  All of the
examples that follow can be viewed this way.


===Window Management


The code that displays the examples also shows how to manage the 
number of windows that are open.


Look at the show-example block in the code near the end of this script.


The location of the example window is also managed here by keeping 
track of the co-ordinates for the sample. After the sample window 
is moved, the next use will open at the same location.



===Pre-loaded Images


For this script, the image which represented a Portable Network Graphic
definition of an image is held in the script and loaded.


For a small number of graphics, this can achieve some packaging and
performance benefits.


The image "polished" is used through the script to achieve the polished 
steel
look that is one the outer frame.

    backtile polished orange
    button 200x50 "Polished Steel Look" polished 


===Two Basic Functions

Two functions are used to create graphical user interfaces
in REBOL: VIEW and LAYOUT.

The LAYOUT function creates a set of graphical objects.  These
objects are called faces.  You describe faces with words and

values that are put into a block and passed to the LAYOUT function.

The VIEW function displays faces that were previously created by
LAYOUT. The example below shows how the result of
the LAYOUT function is passed to the VIEW function, and the
interface is displayed.

    view layout [
        text "Layout passes its result to View for display."
        button "Ok"
    ]

Click on the above example to view it.

!Note: the block provided to a layout is not normal REBOL code,
it is a dialect of REBOL.  Using a dialect makes it much easier
to express user interfaces.



===Styles

Styles describe faces.  The examples above use the text and
button styles to specify a text line and a button. REBOL has
40 predefined face styles. You can also create your own custom
styles.  Here are a few example styles:

    view layout [
        h1 "Style Examples"
        box brick 240x2
        vtext bold "There are 40 styles built into REBOL."
        button "Great"
        toggle "Press" "Down"
        rotary "Click" "Several" "Times"
        choice "Choose" "Multiple" "Items"
        text-list 120x80 "this is" "a list" "of text"
        across
        check
        radio radio
        led
        arrow
        below
        field "Text Entry"
    ]


The words like backdrop, banner, box, text, and button are styles.

===Facets

Facets let you modify a style.  For instance, you can change the
color, size, text, font, image, edge, background, special
effects, and many other facets of a style.

Facets follow the style name.  Here is an example that shows
how you modify the text style to be bold and navy blue:

    view layout [txt bold navy "Facets are easy to use."]

The words bold and navy are not styles.  They are facets that
modify a style. Facets can appear in any order so you don't
have to remember which goes first.  For example, the line
above could be written as:

    view layout [txt "Facets are easy to use." navy bold]

Many facets that can be specified.  Here is an example that
creates bold red text centered in a black box.

    view layout [txt 300 bold red black center "Red Text"]

You can create facets that produce special effects, such
as a gradient colored backdrop behind the text:

    view layout [
        vtext bold "Wild Thing" effect [gradient 200.0.0 0.0.200]
    ]

===Custom Styles

Custom styles are shortcuts that save time.  When you define a
custom style, the facets you need go into the new style.  This
reduces what you need to specify each time you use the style,
and it allows you to modify the look of your interface by
changing the style definitions.

For example, here is a layout that defines a style for red
buttons.  The style word defines the new style, followed by
the old style name and its facets.

    view layout [
        style red-btn button red
        text "Testing red button style:"
        red-btn "Test"
        red-btn "Red"
    ]

So, if you wanted to create a text style for big, bold,
underlined, yellow, typewriter text:

    view layout [
        style yell tt 220 bold underline yellow font-size 16
        yell "Hello"
        yell "This is big old text."
        yell "Goodbye"
    ]


===Master Stylesheet 

REBOL holds its styles in a master stylesheet. When you are
sure that you want to share them without having to add the
style sheet line then do it as follows:

First add the style to the master sheet:

    button 200x50 "Define text-note as maroon bold text" [stylize/master 
    [
        text-note: txt maroon bold      
    ]]

    button 200x50 "Define text-note as white italic text" [stylize/master 
    [
        text-note: txt white italic     
    ]]

Then invoke it:

    view layout [
        across
        size 200x200

        return text-note "This shows a master stylesheet style in use." 

        return text-note "This shows another usage of the same style."

        return text-note "If you want to see the other style displayed, click 
        the Add Style section again and then use the other button"
    ]
    
    
===Note About Examples

!From this point forward, all examples will assume that
the view and layout functions are provided.  Only the layout
block contents will be shown.  To use these examples in your
scripts, you will need to put them in a layout block, as was
shown earlier.

For example, code that is written as:

    view layout [button red "Test it"]

will now appear as:

    button red "Test it"


===Face Sizes

The size of a face depends on its style.  Most styles, such as
buttons, toggles, boxes, checks, text-lists, and fields, have a
convenient default size.  Here are some examples.

    button "Button"
    toggle "Toggle"
    box blue
    field
    text-list

If no size is given, text will automatically compute its size,
and images will use whatever their source size is:

    text "Short text line"
    text "This is a much longer line of text than that above."
    image %palms.jpg

You can change the size of any face by providing a size facet.
The size can be an integer or a pair.  An integer specifies
the width of the face.  A pair specifies both width and height.
Images will be stretched to fit the size.

    button 200 "Big Button"
    button 200x100 "Huge Button"
    image %palms.jpg 50x50
    image %palms.jpg 150x50

===Color Facets

Most styles have a default color.  For example the body of
buttons will default to a teal color.  To modify the color of
a face, provide a color facet:

    button blue "Blue Button"
    h2 red "Red Heading"
    image %palms.jpg orange

Colors can also be specifed as tuples. Each tuple contains three
numbers: the red, green, and blue components of the color. Each
component can range from 0 to 255. For example:

    button 200.0.200 "Red + Blue = Magenta" 200
    image %palms.jpg 0.200.200 "Green + Blue"

Some face styles also allow more than one color.  The effect of
the color depends on the style.  For text styles the first color
will be used for the text and the second color for the background
of the text:

    txt "Yellow on red background" yellow red
    banner "White on Navy Blue" white navy

For other styles, the body of the face is the first color, and
the second color will be used as its alternate.

    button "Multicolor" olive red
    toggle "Multicolor" blue orange
===Layout Commands


To drop user interface elements on the canvas according to VIDs 
directional layout controls 

---Across

You are placing elements in a row orientation
    
    across 
    return button "A" button "B" button "C"
    return button "D" button "E" button "F"
    

---Below

You are placing elements in a column orientation

    below 
    return button "A" button "B" button "C"
    return button "D" button "E" button "F"

---Mix

You can mix the directional controls 

    across 
    return button "A" button "B" 
    below button "C" 
    across button "D" button "E" button "F"


---Padding


The pad keyword creates extra padding between styles. It uses a pair 
or integer value. When it is an integer, spacing is created either 
horizontally (across) or vertically (below). When it is a pair, the 
spacing will be created both horizontal and vertically. The following 
example illustrates both uses. First, the buttons "one" and "two" 
are padded with an integer representing 40 pixels in one direction. 
Then the buttons "three" and "four" are padded with a pair representing 
40x40 pixels. 

    across 
    button "one" pad 40 button "two" return 
    button "three" pad 40x40 button "four" 


Padding can be negative.
    
        backtile polished orange
        pad 200x200 button "A"
        pad -100x-100 button "B"
        
---Guide

A guide is a virtual alignment control

      title "Buttons Without A Guide" 
    button "one"   button "two"  return 
    button "three" button "four" return 
    button" five" button "six" 

With an implicit guide location

    title "Buttons With An Implicit Guide Location" 
    guide 
    button "one"   button "two"  return 
    button "three" button "four" return 
    button" five" button "six" 

With an explicit guide location

    across title "Buttons With An Explicit Guide Location"
    guide 55x100 
    button "one"   button "two"  return 
    button "three" button "four" return 
    button" five" button "six" 
    
===Tabstops

Tabs can be used for alignment.

---Across

    tabs 200 ; sets tabs every 200 pixels   
    across button 20 "A" tab button 20 "B" tab button 20 "C" 
    tabs 100 ; sets tabs every 100 pixels   
    return button 20 "D" tab button 20 "E" tab button 20 "F"
    
---Below

    tabs 200 ; sets tabs every 200 pixels   
    below button 20 "A" tab button 20 "B" tab button 20 "C" 
    tabs 100 ; sets tabs every 100 pixels   
    return button 20 "D" tab button 20 "E" tab button 20 "F"

---Explicit Settings

Tabstops can be set at explicit values 

    tabs [100 124  166 212 300]

    across tab button 20 "A" tab button 20 "B" tab button 20 "C" tab 
    button 20 "D"
    
===Color Facets

Most styles have a default color.  For example the body of
buttons will default to a teal color.  To modify the color of
a face, provide a color facet:

    button 200 blue "Blue Button"
    h2 red "Red Heading"
    image polished orange

Colors can also be specifed as tuples. Each tuple contains three
numbers: the red, green, and blue components of the color. Each
component can range from 0 to 255. For example:

    button 200.0.200 "Red + Blue = Magenta" 200
    image polished 0.200.200 "Green + Blue"


Some face styles also allow more than one color.  The effect of the 
color depends on the style.  For text styles the first color will 
be used for the text and the second color for the background of the 
text:

    txt "Yellow on red background" yellow red
    title "White on Navy Blue" white navy


For other styles, the body of the face is the first color, and the 
second color will be used as its alternate.

    button 200 "Multicolor" olive red
    toggle 200 "Multicolor" blue orange


From the mailing list, there was a problem reported in changing button 
color:

    view layout [
        b: button "New color" [
            b/color: random 255.255.255 
            show b
        ]
    ]
    

And the answer was that the gradient of the color was preventing 
this change from working:


    style color-changing-button button 0.0.0        ; new style overwrites 
    gradient effect
    b: color-changing-button "New color" [
        b/color: random 255.255.255 
        show b
    ]

===Text Facets


Most faces will accept text to be displayed.  Even graphical faces 
can display text.  For example, the box and image faces will display 
text if it is provided:

    box blue "Box Face"
    image polished "Image Face"


Most button faces will accept more than one text string. The strings 
will be shown as alternates as the face is selected.

    button 200 "Up" "Down"
    toggle 200 "Off" "On"
    rotary 200 "Red" "Green" "Blue" "Yellow"
    choice 200 "Monday" "Tuesday" "Wednesday" "Thursday" "Friday"

    text-list 200 "Monday" "Tuesday" "Wednesday" "Thursday" "Friday"


When other datatypes need to be displayed as text, use the form function 
to convert them first:

    button 250 form now
    field form first read %.
    
===Normal Text Style


Normal text is light on dark and can include a number of facets to 
set the font, style, color, shadow, spacing, tabbing, and other attributes.

    text "Normal"
    text "Bold" bold
    text "Italic" italic
    text "Underline" underline
    text "Bold italic underline" bold italic underline
    text "Big" font-size 32
    text "Serif style text" font-name font-serif
    text "Spaced text" font [space: 5x0]

Text also includes these predefined styles:

    title "Title" 200
    vh1 "vh1"
    vh2 "vh2"
    vh3 "vh3"
    vh4 "vh4"
    label "Label"
    
    
===Document Text Style


Document text is dark on light and can also include a number of facets 
to set the font, style, color, shadow, spacing, tabbing, and other 
attributes.

    txt "Normal"
    txt "Bold" bold
    txt "Italic" italic
    txt "Underline" underline
    txt "Bold italic underline" bold italic underline
    txt "Big" font-size 32
    txt "Serif style text" font-name font-serif
    txt "Spaced text" font [space: 5x0]

Document text also includes these predefined styles:

    title "Centered title" 200
    h1 "Heading 1"
    h2 "Heading 2"
    h3 "Heading 3"
    h4 "Heading 4"
    tt "Typewriter text"
===Text Entry Fields


Text input fields accept text until the enter or tab key is pressed. 
 A text input field can be created with:

    field

To make the field larger or smaller, provide a width:

    field 30
    field 300

Fields will scroll when necessary.


Larger amounts of text can be entered in an area.  Areas also accept 
an enter key and will break lines.

    area

You can also specify the area size:

    area 160x200


To force the text in an area to wrap rather than scroll horizontally, 
provide the wrap option:

    area wrap
===Text Setting


To set the value of a text field under program control, use /text: 
e.g.

    across backtile polished
    return t1: txt      200 "This is some original text"
    return f1: field    200 "Some field text"   
    return a1: area  {Some original area text.} wrap 200x80
    return button 200 "Change Text" [
        t1/text: "Some different text" 
        f1/text: "Some new field text"

        a1/text: {Some wrapping text in the^/ area field to^/ show that this^/ 
        is supported}
        show [t1 f1 a1]
    ]
    
===Text Lists

Text lists are easy to create.  Here is an example.

    text-list "Eureka" "Ukiah" "Mendocino"

You can also provide it as a block:

    text-list data ["Eureka" "Ukiah" "Mendocino"]


Almost any type of block can be provided. Here is a list of all the 
files in your current directory:

    text-list data read %.

Here is a list of all the words REBOL has scanned:

    text-list data first system/words
===Scrolling Text List


A style to allow maintenance of lists from Brett Handley on the REBOL 
list:

        style updatable-text-list text-list
        with [
            update-slider: does [
                sld/redrag lc / max 1 length? head lines
            ]
        ]

        tl: updatable-text-list 300x100 data copy system/locale/months
        button  300x20 "Delete first entry on the list" [
            remove tl/data tl/update-slider show tl
        ]
        button 300x20 "Append the 'now' timestamp to list" [
            append tl/data mold now tl/update-slider show tl
        ]
===Text List Picked Values

    list-of-letters: text-list "a" "b" "c" "d" "e" 
    button 200  "Pick Item 3" [
        clear list-of-letters/picked 

        append list-of-letters/picked pick list-of-letters/data 3 
        show list-of-letters
    ]
===Images

By default an image will be scaled to fit within a face.

    image 60x60 polished
    image polished red

Images can be framed in a number of ways:

    image 100x100 polished frame blue 5x5
    image 100x100 polished bevel
    image 100x100 polished ibevel 6x6

Most other faces can accept an image as well as text:

    box 100x100 polished
    button "Button" polished purple
    toggle "Toggle" polished blue red
    field bold  "This is a field." polished effect [emboss tile]

    field bold "This is another field." polished effect [brighten 100]

The image can be provided as a filename, URL, or image data.



===Backdrops

A backdrop can be a color, an effect, an image, or a combination
of the three.  For example a backdrop color would be written as:

    backdrop navy
    title "Color Backdrop" gold

To create a backdrop effect provide it on the line:

    backdrop effect [gradient 1x1 0.0.100 100.0.0]
    title "Gradient Backdrop" gold

A backdrop image can be a file, URL, or image data:

    backdrop polished
    title "Image Backdrop" red

The backdrop image can be colorized:

    size 400x500 
    backdrop polished blue
    title "Blue Image Backdrop"

The image can include an effect:

    backdrop polished effect [fit gradcol 1x1 100.0.0 0.0.250]
    title "Gradient Image Backdrop"
    
===Backtile

To make a backdrop use a tile effect there are two options:

    backdrop polished effect [tile]
    banner "This shows a backdrop with a tile effect"
    
or

    backtile polished
    banner "This demonstrates backtile"


Note the difference between:

    size 400x500 
    backdrop polished
    banner "Here one image is stretched to cover the canvas"

and

    size 400x500 
    backtile polished
    banner "Here one image is repeated to cover the canvas"
    
===Effect Facets


A range of effects are supported for faces.  All of these effects 
are performed directly on the face when it is rendered. Here are 
examples of a few possible effects in top to bottom then left to 
right order:

    style polished-steel image 80x60 polished 
    polished-steel effect [flip 1x1]
    polished-steel effect [rotate 90]
    polished-steel effect [reflect 1x1]
    polished-steel effect [crop 0x50 120x60 fit]
    polished-steel effect [grayscale]
    polished-steel effect [invert]
    polished-steel effect [difference 200.0.0]
    polished-steel effect [tint 80]
    return
    polished-steel effect [contrast 50]
    polished-steel effect [brighten 50]
    polished-steel effect [sharpen]
    polished-steel effect [blur]
    polished-steel effect [colorize 204.0.0]
    polished-steel effect [gradcol 1x1 150.0.0 0.0.150]
    polished-steel effect [gradmul 0x1 0.100.0]
    polished-steel effect [grayscale emboss]


Effects can be used in combination to create other interesting results. 
 However, keep in mind that the computations are performed in real 
time.  If complex combinations are required, a temporary image should 
be created with the to-image function.


===Actions


An action can be associated with almost any face. To do so, follow 
the face style with a block:

    button "Test" [alert "test"]


The block is used as the body of a function that is passed the face 
and the current value (if the face has one).  For example:

    toggle "Toggle" [alert form value] 
    rotary "A" "B" "C" [alert form value]
    text "Click Here" [alert  face/text]

If a second block is provide, it is used for the alternate
actions (right key):


    button "Click Here" [view/new layout [txt "action"]] [view/new layout 
    [txt "alt-action"]]


Use variables to modify the contents or state of other faces. For 
example, the slider will update the progress bar:

    slider 200x16 [p1/data: value show p1]
    p1: progress

!More action on actions needed...

===Show


After the state is changed for a user interface element, it must 
be re-drawn to be reflected on the user interface canvas.

Accomplish this with the show message.

    backtile polished
    across 
    toggle "Toggle State"  
            [   cybernetics?/data: not cybernetics?/data
                show cybernetics?]  

    return  label "Are you interested in cybernetics?" cybernetics?: 
    check 

One show command can be used for multiple user interface elements

        backtile polished orange
        across
        b1: check label "Red" return
        b2: check label "Green" return

        button 200 "Change State But No Refresh" [b1/data: not b1/data b2/data: 
        not b2/data] return
        button "Show" [show [b1 b2]]
===Hide

A user interface element can also be hidden.

        backtile polished orange
        across
        c1: check 
        hide-button: button "Hide" [hide c1] return
        show-button: button "Show" [show [c1 d2]]


The show-button action tries to show a user interface element 'd2' 
that does not exist.
REBOL/View ignores these.
===Invisible Faces


To make a button invisible when the view is opened, you can define 
an invisible button style

This approach sets the show? value to false when the user interface 
element is initialized.

    across

    style invisible-button button with [append init [show?: false]]
    late-shower: invisible-button "I'm Here" return
    return button 200 "Show Invisible Button" [show late-shower]
    
This works for the other visible user interface element.

===Focus

A user interface element can programmatically be given the focus.

    across backtile polished 
    button 200 "Set focus to Phone Field" [focus f2] 
    return label "Name: "   f1: field 100 
    return label "Phone: " f2: field 100 

    return button 200 "Remove focus from Phone Field" [unfocus f2] 
    return button 200 "Hide the Phone Field" [hide f2] return

---Focus Defect


!Note that the tab function shows a hidden field. I have assumed 
that this is a defect. If a field is hidden, the tab button should 
not make it visible. This has been previously sent to feedback.

===Radio Buttons


A radio button is used to make a choice between mutually exclusive 
values. Your preferred programming language is REBOL or C++ or PL/1 
or APL but it is only one of those.

            across backtile polished

            radio of 'programming-language pad 0x-4 label "REBOL" return

            radio of 'programming-language pad 0x-4 label "C++" return

            radio of 'programming-language pad 0x-4 label "PL/1" return

            radio of 'programming-language pad 0x-4 label "APL" return


To mix two groups of radio buttons on one screen, associate them 
with their groups using the "of 'word". In the above, the grouping 
is 'programming-language.

            across backtile polished

            radio of 'programming-language pad 0x-4 label "Language: REBOL" return

            radio of 'programming-language pad 0x-4 label "Language: C++" return

            radio of 'editor pad 0x-4 label "Editor: TextPad" return

            radio of 'editor pad 0x-4 label "Editor: Notepad" return


The padding in the above is needed to keep the label aligned with 
the radio button.

            across backtile polished orange

            radio of 'programming-language pad 0x-4 label "REBOL" return

            radio of 'programming-language          label "APL" return
            
            
            
            

===Radio Button Settings


A radio button is not very useful unless you can find out what its 
setting is and change that setting under program control.


            across backtile polished orange

            rebol-radio:    radio of 'programming-language  [programming-language: 
            'rebol] pad 0x-4 label "REBOL" return

            apl-radio:      radio of 'programming-language  [programming-language: 
            'apl]         label "APL" return
            button 200 "Toggle radio button" [

                    apl-radio/data: not rebol-radio/data: not rebol-radio/data
                    show [rebol-radio apl-radio]
            ]
            
===Check Box

---Purpose


A check box is used to allow user interface choices where the choices 
are not mutually exclusive.

        across backtile polished orange
        c1: check label "Likes animals" return
        c2: check label "Like Monkees" return
        c3: check label "Like The Animals"
        
---State


A check box is not much good if you can't get and set its state (on 
or off).

        across backtile polished orange
        c1: check label "Likes animals" return
        c2: check label "Like Monkees" return
        
    button "Set State" [
        c1/data: true 
        show c1
        c2/data: false
        show c2
    ]
 
 
===Sensor

---Purpose


A sensor is an invisible user interface element. Using a sensor only 
makes sense in a few instances. 


If you want a keycode action where there is no visible user interface 
element to link the action to then a sensor can be used.


This sensor code adds an Escape or Back or Enter action that will 
close the window. 

    sensor 1x1 keycode [#"^M" #" " #"^(back)" #"^(ESC)"] [unview]


Or if you want to make portions of an image 'hot' instead of putting 
buttons on top of the image, then a sensor will achieve this.

        across backtile polished orange

        txt "Click on the upper left section of the gray image to invoke 
        the sensor action"

        return animage: image 100x100 polished      ; here the image is just 
        the polished area

        at animage/offset sensor 50x50 [alert "You pushed over the sensor"]
        
===Displaying Script Values


If the script has a standard format headings, including custom ones, 
these can be used in the application by picking them from the system/script/header.

        backtile polished
        across banner "About"

        return text font-size 16    rejoin ["Title: "           form system/script/header/title]

        return text font-size 16  rejoin ["Originator: "    form system/script/header/author] 
              

        return text font-size 16  rejoin ["Modifier: "      form system/script/header/modifier]

        return text font-size 16  rejoin ["Version: "       form system/script/header/version]

        return text font-size 16  rejoin ["Updated: "       form system/script/header/date]
        return button "OK" [unview] 

===Toggle


A toggle button represents boolean state - either on or off. The 
button stays down until toggled again.
Colors and text can be paired for "on" and "off" state.

    toggle "Up" "Down" red blue

To set the state via program control, use:

        across backtile polished
        return t1: toggle "Up" "Down" red blue
        return button polished 204.0.0 100 "Toggle State" [
            t1/state: not t1/state
            show t1
        ]


===Rotary Buttons


Rotary buttons are a different sort of user interface device. They 
can cause some challenges because the state is what's showing so 
you have to blindly "toggle" to get to a state that you want.  But 
for quick and easy uses where the user is familiar with the options, 
they can be handy.  If you plan to use them for a long list of items 
such as shown  below, they might give you some usability concerns.


---Example

        across backtile polished
        rotary data ["First" "Second" "Third"]

---Setting State

        across backtile polished

        return r1: rotary data (my-options: ["First" "Second" "Third"])
        return button 200 "Change Rotary State" [
            r1/data: next r1/data
            if tail? r1/data [r1/data: head r1/data]
            show r1
        ]

---Example - Usability For Unfamiliar List Contents


The rotary button demonstrated here contains some information unfamiliar 
to most (Saturn's satellites). Use it to to set the state so that 
"Calypso" is set. Doable but without knowing the order each re-paint 
has to be checked to ensure that it is not "Calypso" before clicking 
again.  If you do click past the choice that you want, there is no 
back function so you have to cycle through again.

        return rotary data [

            "Pan" "Atlas" "Prometheus" "Pandora" "Epimetheus" "Janus" "Mimas" 
            "Enceladus" "Tethys" "Telesto" "Calypso" "Dione" "Helene" "Rhea" 
            "Titan" "Hyperion" "Iapetus" "Phoebe"        
        ]


===Arrows


REBOL/View supports arrows as simple user interface elements. Actions 
can be associated with them.



---Arrowheads And Actions

By default, the arrow is 20x20

    across size 200x100 
    backtile polished
    at 50x50 arrow left 
        [alert "You pressed the left arrow"] 

        [alert "You pushed the alternate button on the left arrow"] 
    at 70x30 arrow up
    at 90x50 arrow right [alert "You pressed the right arrow"]
    at 70x70 arrow down
    
---Very Sharp Arrows


And with a little work the arrows and boxes can be merged to look 
sharper. Here is a "sharp at both ends" arrow from the block diagram 
script by Carl:

    origin 0
    backcolor white
    at 0x0 box 40x40 white effect [arrow rotate 270]
    at 110x0 box 40x40 white effect [arrow rotate 90]
    at 24x10 box black 100x20
    
---Arrow Blend

So that shows you how to make an arrow blend into your background

    size 100x100
    across backdrop gray
    at 50x50 box 40x40 gray effect [arrow rotate 90]
    at 40x67 box 25x5 black
    
===LED

LEDs would be used to display state (on or off).  

Clicking the LED toggles its state and changes its color.

LEDs do not support alternate mouse button actions.

    across banner "Light Emitting Diode"
    return 

    l1: led 10x10 [alert "LED left mouse action"] label "Alert status"

    l2: led 10x10 [alert "LED left mouse action"] label "Network status"
    return button "Change state" [
        l1/data: not l1/data
        l2/data: not l2/data 
        show [l1 l2]        
    ]
    
===Box


---Boxing

Draw boxes of any heigth and width with the box style

    box "Large Box" 200x400 polished orange
    
---Boxes As Lines


If you make the box narrow enough or short enough it is a line (or 
a dot).

    across size 300x300 backtile polished
    at 50x0 box 3x100 gold
    at 0x50 b1: box 100x3 gold
    at 10x10 box 5x5 red
    
---Boxes Can Grow

    across size 300x300 backtile polished
    at 150x0 b1: box 100x3 gold
    return pad 0x100 button "Grow Down" [
        for i 3 300 1 [
            b1/size/y: 1 + b1/size/y
            wait 00:00:00.01
            show b1
        ]
    ]

    return pad 0x100 button "Back Up" [
        for i 300 3 -1 [
            b1/size/y: b1/size/y - 1
            wait 00:00:00.01
            show b1
        ]
    ]

You might even find a use for it.


---Grid Effect

Not sure of the use for this yet but here is what you can do:


 return box "Grid Lock" with [effect: [grid 20x20 8x8 4x3]] white 
 300x200
 

 return box "Grid Lock" with [effect: [grid 20x20 5x5 3x3]] white 
 - 80 300x200
 
===Frame

Earlier versions of REBOL VID supported frames in layouts such as
view layout [frame "This is the Bay" %bay.jpg]

These are no longer valid.

But frames can be put around some user interface devices:

    image 100x100 polished frame red
    
===List


A list is an iterated sub layout and takes a layout block that uses 
the Visual Interface Dialect. The styles in the layout will be repeated 
until there is no more room to fit them within the list dimensions.


---Why


A face can be iterated to create a number of virtual faces. For instance, 
when displaying a list of ten buttons, each of the buttons does not 
need to be created as a separate object. If the buttons only differ 
by a few facets (such as position, text, and action taken on selection), 
a model face can be created and iterated for its other position. 
This is useful when creating scrolling lists of files and other data 
sets that share the same appearance. 

---Supply


Supply provides the data to the list for an iterated face.

    do [cnt: 0
        list-collection: [aqua sky water]    
    ]
    backtile polished orange
    across
    list-displayed: list 100x72 [
        origin 0 space 0x0 across
        color-field: txt bold 80x24
    ] supply [
            if none? one-color: pick list-collection count [exit]
            face/text: do pick [one-color] index

    ]

    return txt gold 180 "OK ... but not too useful"


---Supply Columns

Maybe adding some more columns would be better.

Here I'll add a column of buttons that display the color name
and a column of text strings in italic.

    do [
        cnt: 0
        list-collection: [aqua sky water gold silver coffee]    
    ]
    backtile polished orange
        across
        list-displayed: list 300x200 [
            origin 0 space 0x0 across
            color-field: txt bold 80x24
            color-button: button 80x24
            pad 5x1
            txt 100 italic
        ] supply [

                if none? one-color: pick list-collection count [exit]
                face/text: do pick [
                    [one-color]
                    [to-string one-color]
                    [rejoin ["  " to-string one-color]]
                    ] index 
    ]
    

    return txt gold 300 {A bit more interesting but the last row repeats 
    to fill the list size. Some of the other VID components will automatically 
    stretch to fit the size needed (such as this txt field) but the list 
    does not behave that way.  You have to make the list size fit its 
    data or make it smaller and add a vertical scroll capability. That 
    is shown a little later on.}

===List With Supplied Data

This example is to show adding action to the list
and adds a horizontal line between the rows.


    do [
        cnt: 0
        list-collection: [aqua sky water gold silver coffee]    
    ]
    backtile polished orange
        across

        list-displayed: list water edge [size: 6x6 color: silver]  350x96 
        [  
            origin 0 space 0x0 across

            color-field: txt 60 [alert rejoin ["You pressed the " face/text " 
            text field"]]
            pad 45x0            

            color-button: button 80 [alert rejoin ["You pressed the " face/text 
            " button"]]
            pad 5x0
            txt 120 italic

            return box 350x1 white      ; this causes a horizontal line to appear 
            between each row

        ] supply [

                if none? one-color: pick list-collection count [exit]
                face/text: do pick [
                    [one-color]
                    [to-string one-color]
                    [rejoin ["  " to-string one-color]]
                    ] index 
    ]


===Supply List With Scroll

This example shows a supplied list with a scroll capability.
More colors are added to demonstrate scrolling.

Note that this is a verbose list of code where I added comments
for my understanding of how the scroll was linked to the list.
The same effect can be accomplished with fewer lines of code.
    

    do [    ; first this do block creates the data definitions needed.
        slider-position-clicked:  0
        count: 0    
        x: 450
        y: 300

        row-y: 16           ; the row height includes the data plus any separator 
        lines 

        list-size: to-pair reduce [x y]     ; this is the size of the display 
        list  
        separator-size: to-pair reduce [x 1]
        slider-size: to-pair reduce [24 y ]
        list-collection: [

            aqua           bar-color   base-color     beige         black    
                  blue           brick          brown      

        button-color   coal        coffee         crimson       cyan     
              forest         gold           gray       

        green          ivory       khaki          leaf          linen    
              magenta        main-color     maroon     

        mint           navy        oldrab         olive         orange   
              over-color     papaya         pewter         

            pink           purple      rebolor        red           sienna   
                  silver         sky            snow

        tan            teal        violet         water         wheat    
              white          yellow        
        ]    
        
        supply-style: stylize [

                button-fixed: button left coal to-pair reduce [80 row-y]        ; 
                these keep the row elements the same height

                text-fixed: txt to-pair reduce [160 row-y]          
        ]
        
        data-size: length? list-collection  
    ]
    

    backtile polished orange                        ; this section layouts 
    out the list
        
        across

        list-position: at                                   ; the position 
        is captured here in order to later put the slider beside it
        list-displayed: list linen 
            edge [size: 6x6 color: tan]  list-size [  
            origin 0 space 0x0 across
            styles supply-style

            text-fixed [alert rejoin ["You pressed the " face/text " text field"]]

            button-fixed [alert rejoin ["You pressed the " face/text " button"]]
            pad 5x0 

            text-fixed 80 italic [alert rejoin ["You pressed the italic " face/text 
            " text field"]]

            return box separator-size gray      ; this causes a horizontal line 
            to appear between each row

        ] supply [
                count: count + slider-position-clicked  

                if none? one-color: pick list-collection count [exit]
        face/text: 
            either count > (1 + data-size) 
            [""]
            [
                             do pick [

                                    [one-color]                                                      
                                           ; this is supplied to the first txt field (text-fixed)

                                    [to-string one-color]                                           ; 
                                    this is supplied to the button (button-fixed)

                                    [rejoin ["  " to-string one-color " "]]     ; this value is supplied 
                                    to the last text-fixed field
                            ] index 
                    ]
        ]


        ; now add a slider to the side of the list



        at list-position + (list-size * 1x0)                             
           ; this finds the top right border of the list widget
        vertical-slider: slider slider-size to-integer y / row-y
        [

                    slider-position-clicked: vertical-slider/data   ; the slider has 
                    to be bound to the size of the list                

                        * ((1 + data-size) - ((y / (1 + row-y))))       ; including the row 
                        height
                    if slider-position-clicked <> count [
                        count: slider-position-clicked 
                        show list-displayed
                    ]
                ]


===Slider


A slider is interactive user interface element. The data of a slider 
varies from 0 to 1.

    backtile polished   orange across
    slider-1: slider 200x40 
    return button 200 "Move first slider to 50%" [
        slider-1/data: .5 
        show slider-1
    ]

    return txt 200 "The second slider in this example is initialized 
    to the 80% mark."  
    return slider 200x40 with [append init [data: .8]]
    
===Progress Indicator


The progress-1 face in this example is a progress indicator. Because 
it is only displaying information, it is non-interactive i.e. you 
can not change its value by dragging its edges.  The alternate button 
is not supported on a progress indicator.

    backtile polished   orange across
    slider 200x40 [
        progress-1/data: value 
        field-1/text: join (to-integer (100 * value)) " %"
        show [progress-1 field-1]
    ] 
    return progress-1: progress
    return field-1: field
===Panels 


Panels are used to create sub-panes that can be more easily managed 
by grouping

the user interface devices on a panel. The first example below shows 
how to use panels for layout alignment. By creating a panel definition, 
all of the components defined within it are aligned relative to its 
origin.

    across backtile polished brick
    tabs 50
    return panel-1: panel 250x120 [
        backtile polished
        across
        return button water 200 "Button A"
        return button aqua  200 "Button B"
        return button sky   200 "Button C" 
    ]


    at panel-1/offset + panel-1/size panel 60x90 [  ; start at the bottom 
    right corner of panel-1
        backtile polished
        across
        return button tan       20 "1"
        return button coffee    20 "2"
    ]
    
---Multiple SubPanels example


This example from the REBOL html documentation shows how to easily 
hide and show sections of a user interface by displaying them on 
the face area of a box.  


        do [                                ; define two panels
            panel1: layout [
                    origin 8x8
                    h2 "Panel 1"
                    field "Field 1"
                    field "Field 2"
                    button "The Answer" [alert "I know nothing."]
            ]


            panel2: layout [
                origin 8x8
                    h2 "Panel 2"
                    across
                    txt "X:"
                    slider 150x16
                    return
                    txt "Y:"
                    slider 150x16
                    return
                    check [panel2/color: maroon  show panel2]
                    txt "Don't click this"
                    return 
                    check [panel2/color: silver  show panel2]
                    txt "Click this" 
                    return
                ]

                panel1/offset: 0x0
                panel2/offset: 0x0
        ]


        vh2 "Subpanel Examples"     ; now demonstrate panel use
        guide
        pad 20
        button "Panel 1" [panels/pane: panel1  show panels]
        button "Panel 2" [panels/pane: panel2  show panels]
        button "Quit" [unview]
        return
        box 2x140 maroon
        return
        panels: box 220x140
        do [panels/pane: panel1]
        
===Simple Default Style Override


The style's default look can be overriden easily with one line of 
code. 


For example, to make the default button size 200x200 with a water 
color, use

    style button button 200x200 water
    button "Big Blue Button" [unview]

To make the toggle some different default colors:

    style toggle toggle crimson sky
    toggle "Up" "Down"


Note that these stay in effect until they are overridden so if you 
use the default values, exercise some care unless you meant to do 
that. 



===Image Maker


An option used by Carl in some of his programs is to let View create 
specific icons so that you have portability and more control of look 
of the image then if you referenced an external file such as gif 
that was a bullet display. Here's how to do that:

    do [    
        make-image: func [xy wh eff] [
            eff: layout [
                size 20x20 at xy
                box wh effect eff
            ]
        eff/color: rebolor
        to-image eff
        ]


        dot: make-image 6x5 9x9 [gradient 1x1 255.0.0 0.0.0 oval key 0.0.0]

        dot-big: make-image 8x7 12x12 [gradient 1x1 255.0.0 0.0.0 oval key 
        0.0.0]
        arr: make-image 3x3 14x14 [arrow 0.0.127 rotate 90]
        ard: make-image 3x3 14x14 [arrow 0.0.127 rotate 180]    

    ]   ; end of "do" - it is needed here because easyvid approach is 
    expecting vid dialect commands

    banner "Presentation Points"
    size 400x300 across

    style label label gold     ; make a label's text be a different color 
    than the default
    return image dot label "This is bullet point number 1" 
    return image dot label "This is bullet point number 2"
    return image arr label "This is arrow point number 1"

    return image ard label "This is an arrow making a different point"

    return image dot-big pad 0x4 area 300x80 wrap "And because these 
    arrows and dots are images, action can be added to them to make them 
    'hot' with mouse actions including 'over'."
    
===Needs Some Work

!More to come.  These still need to be covered in this
tutorial:

    text-list data [
        icon
    ]
    
===Digital Clock

    origin 0
    banner "00:00:00" rate 1 effect [gradient 0x1 0.0.150 0.0.50]

        feel [engage: func [face act evt] [face/text: now/time  show face]]


 


===REBOL Logo

 image %rebo-logo.gif [unview]

===Paint Drops

REBOL one liner by Vincent Ecuyer


 b: box rate 9 effect[draw[pen(random snow)circle(random 99x99)2]blur]box 
 1x1 rate 9 effect[draw[(b/image: to-image b)]]
 
===eMailer

One line emailer by Doc Kimbel

Assumes you have set up your email in set-user



 e: field "Email" s: field "Subject" m: area "Body" btn "Send"[send/subject 
 to-email e/text m/text s/text alert "ok"]
 
===Hello World

 text "Hello World!" button "Close" [unview]
===Three Buttons

 button "Yes" button "Maybe" button "No"

===View Web Text

 text 800x600 read http://www.rebol.com
 
===View Image

 image %palms.jpg
 
===View Image and File Name


Here a do block is used to initialize the file variable within the 
layout code.

 do [file: %palms.jpg]
 image file  text form file
 
 
===View Image behind File Name


Here a do block is used to initialize the file variable within the 
layout code.

 do [file: %palms.jpg]

 image file form file
 
 
===Buttons From Images

    backdrop 40.70.140
    stat: text bold "Click a Button" 100x20 240.140.40 center
    button "Bay Test"  %bay.jpg 100x100 [
        stat/text: "Upper" 
        show stat
    ]
    button "Blue Test" %bay.jpg 100x100 10.30.180 [
        stat/text: "Lower" 
        show stat
    ]
===View List


 list blue 320x200 [across text white 200 text white 100] data [
    ["John" 100] 
    ["Joe" 200] 
    ["Martin" 300]
 ]
===Movie Credits



    backdrop %bay.jpg effect [fit]

    text center bold 240x30 "REBOL, The Movie" yellow font [size: 16]
    credits: text {

 Edit This File 

 To Add Your Own Credits 
 

 It is very simple to do. 

 Only takes a minute. 

 Only REBOL Makes It Possible...

 } white bold center 240x180 rate 30 para [origin: 0x+100]
        feel [engage: func [f a e] [

            if a = 'time [f/para/origin: f/para/origin - 0x1 show f]
        ]
    ]



===Fire Demo

    box 150x150 with [
        edge: none
        img: image: make image! 150x150
        rate: 20
        text: "FIREBOLEK"
        font: make font [size: 24 color: 255.125.0]

        basic: [draw [image make pair! reduce [(random 3)  - 2 -1] img]]
        effects: reduce [
            append copy basic [blur luma -10]
            append copy basic [sharpen luma -10 blur]
            append copy basic [contrast 10 blur luma -5]        
        ]
        effect: first effects
        feel: make feel [
            engage: func [f a e][
                switch a [

                    down [f/effects: next f/effects if tail? f/effects [f/effects: head 
                    f/effects] f/effect: first f/effects show f]

                    time [show f repeat i f/size/x - 4 [poke f/image (f/size/x * f/size/y) 
                    - i - 2 (random 255.0.0 + random 0.127.0) * 3] f/img: to-image f] 
                           
                ]       
            ]
        ]
    ]
    text 150 {classical fire demo for REBOL^/
 press on fire to see other effects.^/   
 Written by ReBolek, 2001 in 15 mins.^/
 We need new category on Assembly:^/
 less-than-kb-demo ;-)} with [font: make font  [size: 9]]
===Bezier 

Oldes Bezier Line Demo

See script library for %bezier-curve.r

Uses functions and data initialized at script startup

The end points are draggable to change the curve!!!!


Here a do block is used to allow executable lines for initialization 
purposes.

 do [

    draw-beziere-curve: has [result pp x0 x1 x2 x3 y0 y1 y2 y3 cx bx 
    ax cy by ay t tx ty s] [
    result: make block! 120
    pp: p0/size/x / 2
    x0: p0/offset/x + pp
    y0: p0/offset/y + pp
    x1: p1/offset/x + pp
    y1: p1/offset/y + pp
    x2: p2/offset/x + pp
    y2: p2/offset/y + pp 
    x3: p3/offset/x + pp
    y3: p3/offset/y + pp

    insert result compose [
        pen 155.0.0
        line (p0/offset + pp) (p1/offset + pp)
        line (p2/offset + pp) (p3/offset + pp)
        pen 255.255.255 line (p0/offset + pp)
    ]    
    cx: 3 * (x1 - x0)
    bx: 3 * (x2 - x1) - cx
    ax: x3 - x0 - cx - bx
    cy: 3 * (y1 - y0)
    by: 3 * (y2 - y1) - cy
    ay: y3 - y0 - cy - by
    
    t: s: 0.01 ;this value sets quality of the curve
    
    while [t <= 1][
        tx: to integer! (

                (ax * (t * t * t)) + (bx * (t * t)) + (cx * t) + .5
            ) + x0
        ty: to integer! (

                (ay * (t * t * t)) + (by * (t * t)) + (cy * t) + .5
            ) + y0

        t: t + s
        insert tail result to pair! reduce [tx ty]
    ]
    return result
 ]


 click?: false
 mouse-pos: 0x0


 ]

    origin 0

    bkg: box black 400x400 with [effect: reduce ['draw make block! 120]]
    style point box 10x10 with [

        effect: [draw [pen 0.255.0 fill-pen 0.200.0 circle 4x4 4]]
        changes: [offset]
        feel: make feel [
            engage: func [f a e][
                if a = 'down [click?: on mouse-pos: e/offset]
                if a = 'up   [click?: off]
                if find [over away] a [
                    if click? [
                        f/offset: f/offset + e/offset - mouse-pos
                        bkg/effect/2: draw-beziere-curve
                        show [bkg f]
                    ]
                ]
            ]
        ]
    ]
    at 300x200 p0: point
    at 200x100 p1: point
    at 200x300 p2: point
    at 100x200 p3: point
    do [bkg/effect/2: draw-beziere-curve]
                   
===Buttons Galore

Buttons galore from the library script %buttons.r


Here a do block is used to execute the initialization needed within 
the layout block.



    do [
        group: ["rotary" "test" "button"]
    ]

    origin 20x10
    backdrop effect [gradient 0x1 100.20.0]

    vh1 "52 Button Click-up - Each with a different click effect..."

    vtext bold "Here is a small sampling of the thousands of button effects 
    you can create. (This is 78 lines of code.)"
    at 20x80 guide
    button "simple"
    button form now/date
    button "colored" 100.0.0
    button "text colored" font [colors: [255.80.80 80.200.80]]
    button with [texts: ["up text" "down text"]]
    button "bi-colored" colors [0.150.100 150.20.20]

    button with [texts: ["up color" "down color"] colors: [0.150.100 
    150.20.20]]
    button "image" pic
    button "color image" pic 200.100.50

    button "flip color" pic with [effects: [[fit colorize 50.50.200][fit 
    colorize 200.50.50]]]
    button "blink" with [rate: 2 colors: [160.40.40 40.160.40]]
    return

    button "multiply" pic with [effects: [[fit][fit multiply 128.80.60]]]
    button "brighten" pic with [effects: [[fit][fit luma 80]]]

    button "contrast" pic with [effects: [[fit][fit contrast 80]]]
    button "horiz flip" pic with [effects: [[fit][fit flip 1x0]]]

    button "vert reflect" pic with [effects: [[fit][fit reflect 0x1]]]
    button "invert" pic with [effects: [[fit][fit invert]]]

    button "vert grad" with [effects: [[gradient 0x1 0.0.0 0.200.0] [gradient 
    0x1 0.200.0 0.0.0]]]

    button "horiz grad" with [effects: [[gradient 1x0 200.0.0 200.200.200][gradient 
    1x0 200.200.200 200.0.0]]]

    button "both grad" with [effects: [[gradient 1x0 140.0.0 40.40.200] 
    [gradient 0x1 40.40.200 140.0.0]]]

    button "blink grad" with [rate: 4 effects: [[gradient 1x0 0.0.0 0.0.200] 
    [gradient 1x0 0.0.200 0.0.0]]]

    button "blink flip" pic with [rate: 8 effects: [[fit][fit flip 0x1]]]
    return
    button "big dull button with several lines" 100x80 0.0.100

    button "dual color" pic 50.50.100 100.50.50 100x80 with [edge: [color: 
    80.80.80]]

    button "big edge" pic 100x80 with [edge: [size: 5x5 color: 80.80.80] 
    effects: [[fit colorize 50.100.50][fit]]]

    button "oval reflect" pic 50.100.50 100x80 with [effect: [fit reflect 
    1x0 oval]]
    return

    button "text on top" pic 100x80 with [font: [valign: 'top] effects: 
    [[fit gradcol 1x1 200.0.0 0.0.200] [fit gradcol -1x-1 200.0.0 0.0.200]]]

    button "text on bottom" pic 100x80 50.50.100 with [font: [valign: 
    'bottom] effects: [[fit][fit invert]]]

    button "big text font" pic 100x80 with [font: [size: 24] effects: 
    [[fit multiply 50.100.200][fit]]]

    button "cross flip" pic 50.100.50 100x80 with [effect: [fit flip 
    0x1 reflect 0x1 cross]]
    return
    toggle "toggle"
    toggle "toggle red" 100.0.0 
    toggle "toggle up" "toggle down"
    toggle "toggle colored" 0.150.100 150.20.20
    toggle "up color" "down color" 0.150.100 150.20.20

    toggle "toggle multiply" pic with [effects: [[fit][fit multiply 128.80.60]]]

    toggle "toggle contrast" pic with [effects: [[fit][fit contrast 80]]]
    toggle "toggle cross" pic with [effects: [[fit][fit cross]]]

    toggle "toggle v-grad" with [effects: [[gradient 0x1 0.0.0 0.200.0] 
    [gradient 0x1 0.200.0 0.0.0]]]

    toggle "toggle h-grad" with [effects: [[gradient 1x0 200.0.0 200.200.200][gradient 
    1x0 200.200.200 200.0.0]]]

    toggle "toggle both" with [effects: [[gradient 1x0 140.0.0 40.40.200] 
    [gradient 0x1 40.40.200 140.0.0]]]
    return
    rotary data group
    rotary data reduce [now/date now/time]
    rotary data group 100.0.0 0.100.0 0.0.100

    rotary data group with [font: [colors: [255.80.80 80.200.80]]]
    rotary data group with [colors: [0.150.100 150.20.20]]
    rotary data group pic
    rotary data group pic 200.100.50

    rotary data group pic with [effects: [[fit colorize 50.50.200][fit 
    colorize 200.50.50]]]

    rotary data group with [effects: [[gradient 0x1 0.0.0 0.200.0] [gradient 
    0x1 0.200.0 0.0.0]]]

    rotary data group with [effects: [[gradient 1x0 200.0.0 200.200.200][gradient 
    1x0 200.200.200 200.0.0]]]

    rotary data group with [effects: [[gradient 1x0 140.0.0 40.40.200] 
    [gradient 0x1 40.40.200 140.0.0]]]
===Paint Program


This section is a clip of the layout portion of Frank Sievertsen's 
remarkable paint program. Open this example to enable a quick link 
to the real source:


 button "Browse Source" [browse http://www.reboltech.com/library/html/paint.html]
 button "Close" [unview]


In the example below, a DO block is used to execute initialize code.

 do [

    color: fill-color: start: draw-image: draw-pos: tmp: none
    type: 'box
    undos: [] redos: []
    draw: func [offset /local tmp] [
        compose [
            pen (color/color) fill-pen (fill-color/color)
            (type) (start) (either type = 'circle [
                tmp: offset - start
                to-integer square-root add tmp/x ** 2 tmp/y ** 2
            ] [offset])
        ]
    ]
 ]
 
        backdrop effect compose [gradient 1x1 (sky) (water)]
        across
        draw-image: image white 300x300 effect [draw []]
        feel [engage: func [face action event] [
            if all [type start] [
                if find [over away] action [
                    append clear draw-pos draw event/offset
                    show face
                ]
                if action = 'up [
                    append/only undos draw-pos
                    draw-pos: tail draw-pos
                    start: none
                ]
            ]
            if all [type action = 'down] [
                start: event/offset
            ]
        ]]
        do [draw-pos: draw-image/effect/draw]
        guide
        style text text [
            tmp: first back find face/parent-face/pane face
            tmp/feel/engage tmp 'down none
            tmp/feel/engage tmp 'up none
        ]
        label "Tool:" return
        radio [type: 'line] text "Line"
        return
        radio [type: 'box] on text "Box"
        return
        radio [type: 'circle] text "Circle"
        return
        style color-box box 15x15 [

            face/color: either face/color [request-color/color face/color] [request-color]
        ] ibevel
        color: color-box 0.0.0 text "Pen"
        return
        fill-color: color-box text "Fill-pen"
        return
        button "Undo" [if not empty? undos [
            append/only redos copy last undos
            draw-pos: clear last undos
            remove back tail undos
            show draw-image
        ]]
        return
        button "Redo" [if not empty? redos [
            append/only undos draw-pos
            draw-pos: insert draw-pos last redos
            remove back tail redos
            show draw-image
        ]]
===Font Lab

Carl's Font lab



Here a do block is used to initialize some values needed in the layout

 do [

    change-styles: func [style start facet subfacet value /local v][
    start: find style/pane start
    foreach f start [
        f: in f facet
        if subfacet <> 'none [f: in get f subfacet]
        either block? value [

            if not block? get f [set f either none? get f [copy []][reduce [get 
            f]]]

            either v: find get f value [remove v][head insert get f value]
        ][set f value]
    ]
    show style
 ]

 chg: func ['facet 'subfacet value] [
    change-styles external-view norm-start facet subfacet value
 ]
 shad: does [chg font shadow sdir * to-integer sl2/data * 16]
 sdir: 1x1
 sz: 180x40
 sx2: sz/x / 2 
 ]



    style tgl toggle 60
    style lab vtext bold
    backcolor rebolor
    space 0x5
    across 

    p: choice 180 "Sans-Serif Style" "Serif Style" "Fixed Width Style" 

        [chg font name pick reduce [font-sans-serif font-serif font-fixed] 
        index? p/data]
        return
    tgl "Bold" [chg font style [bold]]
    tgl "Italic" italic [chg font style [italic]]
    tgl "Lined" underline [chg font style [underline]]
    return
    tgl "Left" of 'tg1 [chg font align 'left]
    tgl "Center" of 'tg1 [chg font align 'center]
    tgl "Right" of 'tg1 [chg font align 'right]
    return
    tgl "Top" of 'tg2 [chg font valign 'top]
    tgl "Middle" of 'tg2 [chg font valign 'middle]
    tgl "Bottom" of 'tg2 [chg font valign 'bottom]
    return
    lab "Size:" 60x20 font []

    sl: slider 120x20 [chg font size max 8 to-integer sl/data * 40] 
     with [append init [data: .5]]
    
    return
    lab "Space:" 60x20 font []

    sl1: slider 120x20 [chg font space (1x0 * to-integer sl1/data * 20) 
    - 5x0]
    return
    lab "Shadow:" 60x20 font []
    sl2: slider 120x20 [shad]  with [append init [data: .5]]
    return
    lab "Shad Dir:" 60x20
    arrow left  [sdir: sdir * 0x1 + -1x0 shad] pad 6
    arrow right [sdir: sdir * 0x1 + 1x0 shad]  pad 6
    arrow up    [sdir: sdir * 1x0 + 0x-1 shad] pad 6
    arrow down  [sdir: sdir * 1x0 + 0x1 shad]  pad 6
    return
    button sx2 "Text Color" [chg font color request-color]
    button sx2 "Area Color" [chg color none request-color]
    return

    button sx2 "Help" [alert "Click the controls on the left to change 
    text on the right."]
    button sx2 "Close" #"^Q" [unview]
    below
    at p/offset + (p/size * 1x0) + 10x0
    norm-start:
    Title "Title" sz
    h1 "Heading 1" sz
    h2 "Heading 2" sz
    h3 "Heading 3" sz
    h4 "Heading 4" sz
    h5 "Heading 5" sz
    at norm-start/offset + (norm-start/size * 1x0) + 10x0
    banner "Banner" sz
    vh1 "Video Heading 1" sz
    vh2 "Video Heading 2" sz
    vh3 "Video Heading 3" sz
    vtext "Video Text" sz
    text "Document Text" sz
    

===Windows Clipboard


---Cut or Copy to Clipboard


Normal Windows cut and copy commands are supported e.g. on a field, 
contents can be copied to the clipboard. Programmatic access is also 
supported for text contents.

    across 
    label "Entry field: "
    return input-field: field 200 "Enter your text here"

    return button 200 "Copy Entry field data to clipboard" [write clipboard:// 
    input-field/text]

    return button 200 "Show Clipboard Contents" [alert read clipboard://] 


---Clearing The Clipboard


    across 
    button 200 "Clear The Clipboard" [write clipboard:// ""]

    return button 200 "Show Clipboard Contents" [alert read clipboard://] 



---Paste from Clipboard


Normal Windows paste commands are supported e.g. on a field, contents 
can be pasted. Programmatic access is also supported for text contents.

    across 

    button 200 "Show Clipboard Contents" [alert read clipboard://] 
===Requesters


REBOL View supports an assortment of requesters. 


The results of the request-* code are returned as its value e.g. 
chosen-date: request-date


---Request Yes | No | Cancel


Provides the user the capability to pick from choices "Yes" | "No" 
| "Cancel"

The result is "True" | "False" | none

    do [user-response: none]

    button "Simple Request" 200 [user-response: request "Do you want 
    to abandon your input so far?"]
    button "View User Response" 200 [alert form user-response]
    

---Pick A Color

    do [chosen-color: gold] 
    button "Pick Color" 200 [chosen-color: request-color]
    button "View Chosen Color" 200 [alert form chosen-color]



---Pick An Answer

The request allows a descriptive value then 1, 2, or 3 options.


    button "Format" 100 [request ["Your message goes here. It will wrap 
    if it is very very long." "Choice 1" "Choice 2" "Choice 3"]]
    

    button "Example 1" 100 [request ["Pick The Color of Your New Model 
    T" "Black"]]
    

    button "Example 2" 100 [request ["Pick one country" "England" "France"]]


    button "Example 3" 100 [request ["Run Extract Script?" "Yes" "No" 
    "Cancel"]]


---Pick A Date

    do [chosen-date: 01-Jun-1990]
    button "Pick Date" 200 [chosen-date: request-date]
    button "See Chosen Date" 200 [alert form chosen-date]

---Get A LogonID and Password

    do [credentials: none]
    button "Get Credentials" 200 [credentials: request-pass]
    button "View Credentials" 200 [
        view/new layout [
            size 200x200 backtile polished orange 
            across banner "Credentials" 
            return label "LogonID:  " txt pick credentials 1
            return label "Password: " txt pick credentials 2
        ]
    ]


---Pick A File


Format: REQUEST-FILE /title title-line button-text /file name /filter 
filt /keep    

        do [filter-block: ["*.gif" "*.jpg" "*.png" "*.bmp"]]

        button "Pick Any File" 300 [request-file "Select"]      

        button "Pick With A Title" 300 [request-file/title "Pick The Data 
        File to Process" "OK"]

        button "Change the Action Button Name" 300 [request-file/title "Pick 
        The Data File to Process" "OK"]        

        button "Keep Results" 300 [request-file/title/keep "Previous Select 
        On This Button Is Kept" "OK"]

        button "Filter Files" 300 [request-file/title/filter "Pick An Image 
        File" "OK" filter-block]    



---Request Text Input

Format: REQUEST-TEXT /offset xy /title title-text /default str
    

    button "Request Text Input - all default parameters" 300 [request-text]

    button "Request Text Input - with offset to window" 300 [request-text/offset 
    40x40]

    button "Request Text Input - with title" 300 [request-text/title 
    "Input your question"]

    button "Request Text Input - with default" 300 [request-text/default 
    "Key your question here"]

    button "Request Text Input - with all parameters" 300 [request-text/offset/title/default 
    100x100 "Input your question" "Key your question here"]



---Request Download from Net


Request a file download from the net. Show progress. Return none 
on error.

Format: REQUEST-DOWNLOAD url /to local-file

    backtile polished orange    

    button "Request File Download To local REBOL Cache" 300 [request-download 
    http://www.rebol.com/index.html]

    button "Request File Download To This Directory" 300 [request-download/to 
    http://www.rebol.com/index.htmlnone]

    button "Request File Download To Specific File" 300 [request-download/to 
    http://www.rebol.com/index.html%/c/temp.html]

===Message Box


    button "Format" 100 [request ["Your message goes here. It will wrap 
    if it is very very long and tedious." "Close"]] 
    button "Example" 100 [request ["You done good!" "OK"]]



---Confirmation

    button "Exit" 100 [
        request/confirm "Do you want to quit without saving?" []
    ]
    

===Calling the Editor

The REBOL editor is now callable with the editor function

    backtile polished
    button 300 "Create a test file and edit it" [
        write %temp.txt "This is a test file"
        editor %temp.txt
    ] frame 204.0.0 
    

===Calling Windows

With View/Pro the calling of executables is supported.

Here are two simple examples that will work if you have View/Pro 
on a platform where a notepad and calc are avaiable.

    across backtile size 200x200
    return button "Notepad" [call ["notepad.exe"]]
    return button "Calculator" [call ["calc.exe"]]


===Window Options


Note that these are options which are ignored by the easyvid.r code 
that displays them in this tutorial.
Copy the code out and run it standalone in REBOL/View.

---Block Options: No Border and No Title

    view/options layout [
        size 200x200 
        banner "Window Options" 
        button "Close" [unview]
        ] [
            no-border
            no-title
        ]


---Word Option: No Title


Note that the results of this are surprising if you run it from within 
a script that has a title option. It is displayed near location 0x0 
of the resulting window instead of in the window frame that has been 
suppressed. 

    view/options layout [
        size 200x200 
        banner "Window Options" 
        button "Close" [unview]
        ] 'no-title

===REBOL/View Notifiers


REBOL/View supports simple notifiers to send messages to a user interface


---Alert

    button 220 polished "Send alert message" [
        alert "This causes a dialogue box to popup"
    ]





---Flash

Flash is provided to provide a message and keep on processing.

    across size 200x200
    return button 150 "Create Flash Message" [flash "Testing"]
    return button 150 "Unview Flash" [unview]



---Inform

    inform layout  [
        backtile polished sky 

        across text font-size 16 bold underline red "Action complete!" 
        return button "OK"  [unview]]

---Popup

REBOL supports popups  (see note below before running!)

        across size 200x200 
        button "Show Popup" [
            show-popup popup-layout: layout [
                    across size 200x200 
                    backtile polished
                    banner "The Popup Worked" 
                    return button "Unview" [unview]
                ]
        ]
        return button "Hide Popup" [unview/only popup-layout]

I have had some difficulties (process lockup) when using

these popups so just use view layout [...] and skip the popup part.

===Diagram Example


Carl has created some diagrams in REBOL using styles to make an architecture 
diagram.

This is a slightly modified version.


Here again a DO block precedes the layout code for non-layout initiatiation 
... here the definition of a function.

Why make a diagram this way?


1. One reason is that it can be interactive ... the sections are 
all "hot" with a few lines of code.  Here they pop up REBOL Dialogs 
but they could do anything that can be coded even something as simple 
as launching a browser on a different URL for each diagram component. 
 The "Compositor" box demonstrates this by launching your browser 
on the REBOL.com site.


2. Very small footprint size compared to other presentation source 
formats.




 do [
        information: func [info [string!]][
        request/ok reform [ info]
    ]
 ]



    style bx box 255.255.255 0.0.0 font-size 11 font [color: 0.0.0 shadow: 
    0x0] edge [size: 5x2] 
        [request/ok reform ["No information on" face/text]] 

    style bb box bold left top para [origin: 6x10] edge [size: 2x2]
        [request/ok reform ["No information on" face/text]]
    backcolor silver + 30
    at 15x15 h1 486 left "Arch Structure" 
    at 15x50    bb "Client" 506x436 160.80.80 [

        information "Any client machine e.g. branch or Call Centre"]

    at 25x252   bb "Mid-Tier" 486x68 effect [gradient 1x1 169.91.155 
    80.45.75]

    at 25x152   bb "UI" 486x96    effect [gradient 1x1 38.156.82 19.78.41]

    at 25x324   bb "Servers" 486x151   effect [gradient 1x1 103.96.200 
    50.45.100] [

        information "Mid-tiers servers with XYZ relational database server" 
                                                                         
              
    ]

    at 130x216  bx "Compositor" 182x24 bold [browse http://www.rebol.com]

    at 130x60   bx "Browser" 120x24 [information "Branch standard browser"]

    at 130x188  bx "Sound" 182x24 bold [information "Sound services"]
    at 255x60   bx "Win32" 120x24 [information "Win32 App"]

===Column Images


Creates a layout looking (a little) like columns. It uses a gradient 
effect going from darker to lighter

 do [
     column: make image! layout [

            backdrop effect [gradient 1x0 20.20.20 250.240.230 luma 60]
        ]

    column-size: 50x420

    area-size: 400x420  ; height should be the same as column-size
 ]
 backtile polished tan
   across 
   image column-size  column 
   pad -10x0        ; this brings the default VID spacing back
   area wrap area-size  

   edge none        ; take the edge off of area so that it more closely 
   blends 
   shadow 2x2

   pad -10x0 image column-size column  ; if you want a right column

===Tree View of Directory

This is Didier's tree view %request-dir.r


In this sample, you must be online because the code is accessed on 
the Rebol script server

 do [do http://www.rebol.org/library/scripts/request-dir.r
     request-dir
 ]


Note that:

* the script is read from the script library but runs locally

* it is showing the files in your directories


===The emailer Function


The function for emailing has appeared in Jan-2004 on the rebol list.


It is a simple idea ... to create a standard emailer by invoking 
a function emailer. This window will show the source:

  text wrap 400x300 mold get 'emailer

And it is simple to run:

    across size 200x200
    return button 150 "Run emailer" [emailer]


But on my machine there is again a problem - the emailer locks up 
REBOL/View.

Recommendation:

* if it works use it if you like


* use Doc Kimbel's one liner (works for me). Assumes you have set 
up your email in set-user



 e: field "Email" s: field "Subject" m: area "Body" btn "Send"[send/subject 
 to-email e/text m/text s/text alert "ok"]



* better yet, make your own... if the code for the basic is 1 line, 
then a custom version is not far away. Here's an example that allows 
selection of your frequent contacts (entered in the names-addresses 
series) and keeps a journal of email that you have sent (using this 
code) in file email-journal.txt.  Assumes you have setup your user 
profile correctly to allow sending of email.


 do [

  names-addresses: [
    "Contact 1"         [contact1-:-no-such-address-:-com]
    "Contact 2"         [contact2-:-no-such-address-:-com]
    "Contact 3"         [contact3-:-no-such-address-:-com]
  ]

  names: copy []
  foreach [name address] names-addresses [append names name]


  journal?: false  ; set to true if want to journalize sent email
 ]

    e: rotary 200 data sort names
    s: field "Subject" 
    m: area 500x400 wrap "Body" 
    btn "Send"[

        send/subject who-to: select names-addresses e/text m/text s/text 
        alert join "Sent email to: " form who-to
        
        if journal? [
            write/append %email-journal.txt rejoin [
                "[ When-sent: " now/precise 
                " To: " who-to
                " Subject: {" s/text
                "} Message: {" m/text "} ] "
                newline
            ]
        ]
    ]
    btn "Quit" [unview]



It won't take much to change this from the rotary used to a text 
list allowing multiple selections.





===Some More email


Earlier there have been a few examples of sending email. Here are 
a few more that often appear in the mailing list

---Simple Send


This is not a runnable version because you don't need anything but 
REBOL/Core to run it. It has been wrapped in a DO block so it does 
not send errors to the console.

---Quick Send Short Message

 do [
    send [address-:-isp-:-com] "My Message"
 ]
 
---Send Longer Message  

Now a more complex message where there is a body to the message:

 do [
    send [address-:-isp-:-com] {Sample Message
               
    This is the body of the message
    } 
 ]

---Send with One Attachment


Here, so that the sample does not fail, test file(s) are created 
by the code before attempting the send. 

 do [
    test-file: %file-attachment.txt
    write test-file {Just some test data to create a file}
    send/attach [address-:-isp-:-com] {Sample Message
               
    This is the body of the message
    } test-file
 ]
 
---Send with Attachments

And a message with multiple attachments.


Here, so that the sample does not fail, test file(s) are created 
by the code before attempting the send. 

 do [
    files: [%file-attachment.txt %second-attachment.txt]

    foreach file files [write file {Just some test data to create a file}]
    send/attach [address-:-isp-:-com] {Sample Message
               
    This is the body of the message
    } files
 ]
 
---Send to Multiple Addresses


Here, so that the sample does not fail, test file(s) are created 
by the code before attempting the send. 

 do [
    files: [%file-attachment.txt %second-attachment.txt]

    foreach file files [write file {Just some test data to create a file}] 

    send/attach [[address-:-isp-:-com][asecondAddress-:-isp-:-com]] {Sample Message
               
    This is the body of the message
    } files
 ]
 
---Send/only

Same send only just provide the SMTP server with one copy:

Here, so that the sample does not fail, test file(s) are created 
by the code before attempting the send. 

  do [
    files: [%file-attachment.txt %second-attachment.txt]

    foreach file files [write file {Just some test data to create a file}] 

    send/only/attach [[address-:-isp-:-com][asecondAddress-:-isp-:-com]] {Sample 
    Message
               
    This is the body of the message
    } files
 ]
 
---Send With Header


This example uses a Do block to wrap the code. If you execute the 
email should be sent.
But it is unlikely to be delivered.


The addresses for me and you should be changed in your use as well 
as the

* Subject

* Organization

* Content 

 do [
   me: [myaddress-:-isp-:-com]
   you: [youraddress-:-isp-:-com]
   header-object: make system/standard/email [
            From: me
            Reply-To: me
            Subject: "Some Stuff"
            Organization: "Cyberia"
            MIME-Version: 1.0 
            Content-Type: "text/plain"
    ]
 send/header you {Test Message
    This is the message body.
    }                 
    header-object 
 ] 

---Send with CC

This adds a copy value in the header-object

 do [
   me: [myaddress-:-isp-:-com]
   you: [youraddress-:-isp-:-com]
   header-object: make system/standard/email [
            From: me
            Reply-To: me
            Subject: "Some Stuff"
            Organization: "Cyberia"
            MIME-Version: 1.0 
            Content-Type: "text/plain"
        cc: [another-address-:-isp-:-com]
    ]
 send/header you {Test Message
    This is the message body.
    }                 
    header-object 
 ] 


   
---Doctored Code

Again Doc Kimbel's one liner that does not waste a character


 e: field "Email" s: field "Subject" m: area "Body" btn "Send"[send/subject 
 to-email e/text m/text s/text alert "ok"]


===Sharp Styles


I really like the style that Didier has put around his email previewer

 do [
    ss-light: stylize [
        text: text feel none
        vtext: vtext feel none
        col-hdg: text black 255.255.204 bold middle effect []
        col-txt: text edge [size: 1x0 color: gray effect: 'bevel]
        ban: vh3 left to-pair reduce [
            50 logo.gif/size/y] edge [

                color: 0.0.0 size: 0x1] feel none with [color: black]
        lab: label para [origin: 2x3 margin: 0x2]
        labe: lab edge [size: 1x1 color: water effect: 'ibevel]
        inf: info 100 font-color yellow
        bkg: backdrop water - 10.10.10
        txt-big: vtext 300 font-size 18 font-color yellow center
        rti: vtext font-size 14 bold
        txt-ch: rti font-color white 170x22 para [
            origin: 2x3] with [font: make font [
                    color: white] colors: [55.95.155 235.170.55]]
        btnb: btn 70.70.70 font-color white

        men: rti 264 edge [size: 1x1 color: water effect: 'bevel] para [origin: 
        20x2 margin: 1x4]

             with [color: water - 40.40.40 effect: first effects: [

                [draw [pen white fill-pen white polygon 5x2 13x10 5x18]] [draw [pen 
                white fill-pen white polygon 2x5 10x13 18x5]]
             ] feel: none]  ;system/view/vid/vid-feel/hot]

        cbox: box 60x20 edge [size: 1x1 color: water effect: 'bevel] [

            if temp: request-color/color first face/data [face/color: temp change 
            face/data temp show face]
        ] with [append init [color: first data]]
    ]
    stylesheet: ss-heavy: stylize/styles [

        col-hdg: col-hdg effect [gradcol 0x1 200.200.160 155.155.104]

        ban: ban effect [merge gradcol 150.180.200 0.0.0] with [color: none]

        bkg: backdrop effect [gradient 1x1 65.125.175 45.75.115 grid 2000x4 
        1999x4 70.130.190 blur]
        txt-big: vtext 300 font-size 18 font-color yellow center
        rti: vtext font-size 14 bold

        txt-ch: txt-ch effect [gradcol -1x1 105.105.105 151.151.151]
        men: men effect [gradcol -1x0 black water]
    ] ss-light
 ]
    styles stylesheet
    space 4x4 origin 4x4 across
    bkg
    pad 15 ban 235 :title para [origin: 32x0]
    pad -254
    image 30x30 %palms.jpg effect [fit key 255.0.255]
}
code: text: layo: external-view: none
sections: []
layouts: []
space: charset " ^-"
chars: complement charset " ^-^/"

rules: [title some parts]

title: [text-line (title-line: text)]

parts: [
      newline
    | "===" section
    | "---" subsect
    | "!" note
    | example
    | paragraph
]

text-line: [copy text to newline newline]
indented:  [some space thru newline]
paragraph: [copy para some [chars thru newline] (emit txt para)]
note: [copy para some [chars thru newline] (emit-note para)]
example: [
    copy code some [indented | some newline indented]
    (emit-code code)
]

section: [
    text-line (
        append sections text
        append/only layouts layo: copy page-template
        emit h1 text
    ) newline
]
subsect: [text-line (emit h2 text)]
emit: func ['style data] [repend layo [style data]]
emit-code: func [code] [
    remove back tail code
    repend layo ['code 460x-1 trim/auto code 'show-example]
]
emit-note: func [code] [
    remove back tail code
    repend layo ['tnt 460x-1 code]
]

show-example: [

    if external-view [xy: external-view/offset  unview/only external-view]
    xcode: load/all face/text
    if not block? xcode [xcode: reduce [xcode]] ;!!! fix load/all
    if here: select xcode 'layout [xcode: here]
    external-view: view/new/offset layout xcode xy
]

page-template: [
    size 500x480 origin 8x8
    backdrop white - 80

    style code tt snow navy bold as-is para [origin: margin: 12x8]
    style tnt txt maroon bold
]

parse/all detab content rules
show-page: func [i /local blk last-face][
    i: max 1 min length? sections i
    append clear tl/picked pick sections i 
    if blk: pick layouts this-page: i [
        f-box/pane: layout/offset blk 0x0 
        last-face: last f-box/pane/pane    ; bh slider

    f-box/pane/pane/1/size: f-box/pane/size: max 500x480 add 20x20 add 
    last-face/offset last-face/size ; bh slider
    update-slider ; bh slider
        show f-box
    ]

    show tl    ; changed to after slider update ; was not refreshing 
    the index display
]


update-slider: does [
    sld/data: 0
    either object? f-box/pane [
        sld/redrag min 1.0 divide sld/size/2 f-box/pane/size/2
        sld/action: func[face event] compose [

            f-box/pane/offset/2: multiply face/data (subtract 480 f-box/pane/size/2)
            show f-box
        ]
    ][
        sld/redrag 1.0 show sld
        sld/action: none
    ]
    show sld
]

main: layout [
    backtile polished
    across
    vh2 title-line return
    tl: text-list 160x480 bold black white data sections [
        show-page index? find sections value
    ]
    h: at
    f-box: box 500x480

  at h + 500x0 sld: slider 24x480                 ; add brett's slider
    at h + 456x-24
    across space 4
    arrow left  keycode [up left] [show-page this-page - 1]
    arrow right keycode [down right] [show-page this-page + 1]
    pad -150

    txt white italic font-size 16 form system/script/header/date/date
]

show-page 1
xy: main/offset + either system/view/screen-face/size/x > 900 [
    main/size * 1x0 + 8x0][300x300]
view main

parse/all ie [copy one to " "  skip  copy two to " " skip copy three 
to end]

Your verison runs until the end of the series. I just need to skip 
the next 10 entries.

>> parse next s: "ArialBoldItalic" [ some [ some non-caps [ end | 
mark: ( insert mark #" " ) skip ]] ]
== true
>> s
== "Arial Bold Italic"

not sure if correct, but:

caps: charset [ #"A" - #"Z" ]
non-caps: complement caps
s: "aaaArialBoldItalic"

parse/all s [any [mark: caps (insert mark #" ") skip | skip] end]

>> parse next s: "ArialBoldItalicYY" [ some [ some non-caps [ end 
| mark: ( insert mark #" " ) 2 skip ]] ]
== true
>> s
== "Arial Bold Italic YY"

>> parse/all s: "abcArialBoldItalicsCY" [some [mark: caps (insert 
mark #" ") 2 skip | skip] end]
== true
>> s
== "abc Arial Bold Italics CY"

Here's the finished code (which obtains REBOL compatable font names 
under Mac):

	fonts: copy []
	caps: make bitset! [#"A" - #"Z"]

 foreach file compose [(read %/System/Library/Fonts/) (read %/Library/Fonts/)] 
 [
		if %.dfont = suffix? file [
			s: form first parse file "."

   parse next s [any [mark: caps (insert mark #" ") 2 skip | skip] end]
			insert tail fonts s
		]
	]
	remove-each font-name fonts: sort unique fonts [

  (size-text make face [text: "A" font: make face/font [name: font-name 
  size: 10]]) =

  size-text make face [text: "A" font: make face/font [name: font-name 
  size: 12]]
	]


(the windows func to do this is http://www.reboltech.com/library/scripts/get-fonts-windows.r
)

Some time ago, I did form-decimal function too. But I am really a 
coding lamer, so dunno, if it cover at least half the cases other 
versions do. Here it is:

form-decimal: func [num /local tmp main rest sign base][

     either found? find tmp: to-string num "E" [

              parse tmp [
                 [copy main to "." 
                  skip
                  copy rest to "E"
                  |
                  copy rest to "E"
                  (main: copy "")  
                  ]
             
                 skip
                 mark: (sign: copy/part mark 1)
                 skip
                 copy base to end
               ]


        either sign = "-" [

                tmp: copy "0."

                loop ((to-integer base) - 1) [insert tail tmp "0"]
                insert tail tmp rest
        ][
                tmp: copy ""

                insert tail tmp join main rest

                loop ((to-integer base) - (length? rest)) [insert tail tmp "0"]  
                    
                           
        ] 
     
      tmp                 

     ][num] 

]

form-decimal: func [   num     [number!]
        cifre   [integer!]

        /local sign str poscifre int frac pow
    ][   sign: either negative? num [#"-"] [""]
        str: make string! 16
        either zero? num
        [   insert str #"0"
            if cifre > 0
            [   insert/dup
                    insert
                        tail str
                        #","
                    #"0"
                    cifre
        ]   ]
        [   num: abs num
            num: form
                add
                    multiply
                        power 10 cifre
                        to-decimal num
                    0,5

                        ; mainly WINE bug workaround - might also work for larger numbers 
                        on Windows
                        if find num "E"

                        [       parse num [copy int to "." skip copy frac 15 to "E" skip 
                        copy pow to end]
                                pow: to integer! pow
                                either pow >= 0
                                [       insert/dup
                                                insert/part

                                                        insert clear num int
                                                        frac

                                                        skip frac pow
                                                #"0"

                                                pow - length? frac
                                ]
                                [       num: "0"]
                        ]
            clear any [find num "." ""]
            poscifre: skip  tail num  negate cifre
            insert/part insert str sign num
                num: skip num
                    1 + remainder
                        subtract
                            index? poscifre
                            2
                        3
            while [(index? poscifre) > (index? num)]
            [   insert/part
                    insert
                        tail str
                        #"'"
                    num
                    num: skip num 3
            ]
            if empty? str [insert str #"0"]
            if not tail? poscifre
            [   insert
                    insert/dup
                        insert
                            tail str
                            #","
                        #"0"
                        cifre - length? poscifre
                    poscifre
            ]
        ]
        str
    ]

so I will add a comma to the end, then parse data [any [ some digit 
#"/" copy result #"," (insert results result) | skip]]

here is my way:
parse/all {aX--baX~~a--aX~~} [
	"a"
	some [
	    s:
		any [
		    t: ["--" | "~~"] (result: copy/part s t print result) break
			| skip
		]
		thru "a"
	]
	to end
]

Skip tells parse to move to the next item:

>> parse "abcdefghi" ["abcdefgh" skip]
== true   ;; because the skip took us to the end

data: {my string^-"<span style="font: 12px arial;>some text</span>"}

rule: [copy token [to tab | to end](insert/only tail result token) 
skip rule]
parse/all data [(result: copy []) rule]
result


 ["my string" {"<span style="font: 12px arial;>some text</span>"}]

Here's an example of what you could do with the PARSE proposals:

use [r d f] [ ; External words from standard USE statement
    parse f: read d: %./ r: [
        use [d1 f p] [ ; These words override the outer words
            any [
            ; Check for directory filename

                (d1: d) ; This maintains a recursive directory stack
                p: ; Save the position

                change [ ; This rule must be matched before the change happens

                    ; Set f to the filename if it is a directory else fail
                    set f into file! [to end reverse "/" to end]
                    ; f is a directory filename, so process it
                    (

                        d: join d f ; Add the directory name to the current path

                        f: read d   ; Read the directory into a block
                    )
                    ; f is now a block of filenames.
                ] f ; The file is now the block read above
                :p  ; Go back to the saved position
                into block! r ; Now recurse into the new block
                (d: d1) ; Pop the directory stack
            ; Otherwise backtrack and skip
                | skip
            ] ; end any
        ] ; end use
    ] ; end parse
    f ; This is the expanded directory block
]

Here's an revised version with more of the PARSE proposals:

use [r d res] [ ; External words from standard USE statement
    parse res: read d: %./ r: [
        use [ds f] [ ; These words override the outer words
            any [
            ; Check for directory filename

                (ds: d) ; This maintains a recursive directory stack
                [ ; Save the position through alternation

                    change [ ; This rule must be matched before the change happens

                        ; Set f to the filename if it is a directory else fail

                        set f into file! [to end reverse "/" to end]

                        ; f is a directory filename, so process it
                        (

                            d: join d f ; Add the directory name to the current path

                            f: read d   ; Read the directory into a block
                        )
                        ; f is now a block of filenames.
                    ] f ; The file is now the block read above
					fail ; Backtrack to the saved position
					|
					into block! r ; Now recurse into the new block
				]
                (d: ds) ; Pop the directory stack
            ; Otherwise backtrack and skip
                | skip
            ] ; end any
        ] ; end use
    ] ; end parse
    res ; This is the expanded directory block
]

parse/all s [some ["12345" (print "*") end skip]
is that not enough ?

The skip will produce false because it is attempting to skip past 
the end.

The phrase [end skip] will always fail and return false.

For now, you want a continuation variable. Like this:

result: parse [this that bleh blah][some [set w word! (cont: unless 
find words w [[end skip]]) cont]]

continue: none	;means continue is ok
stop: [end skip]

result: parse [this that bleh blah][some [set w word! (unless find 
words w [continue: stop]) continue]]

Is there any better way how to change the main parse rules during 
parse like this one? (just a simple example..in real life the lexers 
would be more complicated :)  
d: charset "0123456789"

lexer1: [copy x 1 skip (probe x if x = "." [lexer: lexer2]) | end 
skip]
lexer2: [copy x some d (probe x lexer: lexer1) | end skip] 
lexer: lexer1
parse "abcd.123efgh" [ some [() lexer]]

I really like REBOL when I'm able to do things like:
c1: context [
	n: 1

 lexer: [copy x 1 skip (prin reform ["in context:" n "=> "] probe 
 x if x = "." [root-lexer: c2/lexer]) | end skip]
]
c2: context [
	n: 2
	d: charset "0123456789"

 lexer: [copy x some d (prin reform ["in context:" n"=> "] probe x 
 root-lexer: c1/lexer) | end skip] 
]
root-lexer: c1/lexer
parse "abcd.123efgh" [ some [() root-lexer]]

This would work in this case but I need to get "2" only if sequence 
before it is exactly previous two "start" "B" XX "end" ...  there 
can be "B" in other places of the string and it musn't take that 
(I am used on using thru and to too but I musn't use them in this 
case for this reason as it might just skip to some "B"

( I need to parse meta tags description and keywords and abstract 
if they exist -- they can come in any order, there can be one or 
multiple spaces/newlines/tabs between tag arguments, there can be 
" or '  used as argument="asdasd" )
>> doc2: {<head>

{    <title>Dragonicum.com - making the right business connections 
!</title>

{    <meta name="keywords" content="Company Directory, Join Us, Advanced 
Search, Trade Leads, Forum, Trade S

{    hows, Advertising, Translation, fair trade, trade portal, business 
to business, trade leads, trade even
{    ts, china export, china manufacturer" />

{    <meta name="description" content="New international trade portal 
and company directory for Asia, Europe

{     and North America. Our priority No.1 is to create and maintain 
a safe, well lit business-to-business m

{    arketplace, by assisting our members in identifying new trustworthy 
business partners!" />

{    <link rel="stylesheet" href="style/blue_main.css" type="text/css" 
/>}
== {<head>

<title>Dragonicum.com - making the right business connections !</title>
<meta name="keywords" content="Company Directory...


>> T: "" parse doc [ thru "<meta" "name=" skip "keywords" skip "content=" 
m: skip (m1: first m ) copy T to m1  to end ] print T

Company Directory, Join Us, Advanced Search, Trade Leads, Forum, 
Trade Shows, Advertising, Translation, fair trade, trade portal, 
business to business, trade
leads, trade events, china export, china manufacturer

>> T: "" parse doc [ thru "<meta" "name=" skip "description" skip 
"content=" m: skip (m1: first m ) copy T to m1  to end ] print T

>>

( as you see because keywords are first it works for them , but doesn't 
for description , they can be in different order in other document 
etc)

>> T: K: D: "" parse doc [ SOME [ thru "<meta" "name=" skip [ "description" 
(V: 'D) | "keywords" (V: 'K)] skip "content=" m: skip (m1: first 
m ) copy T to m1
(set V T) ]  to end ] ?? K ?? D

K: {Company Directory, Join Us, Advanced Search, Trade Leads, Forum, 
Trade Shows, Advertising, Translation, fair trade, trade portal, 
business to business, tr
ade leads, trade events, china export, china manufacturer}

D: {New international trade portal and company directory for Asia, 
Europe and North America. Our priority No.1 is to create and maintain 
a safe, well lit busi

ness-to-business marketplace, by assisting our members in identifying 
new trustworthy business partners!}

== {New international trade portal and company directory for Asia, 
Europe and North America. Our priority No.1 is to create and mai...
>>

Here's absolutly terrible parser - it does NOT follow RFC, allow 
any combination of alpha chars, dots, one @ char, and the same, once 
again to the next space char ...

space: #" "
mailchar: charset [#"0" - #"9" #"A" - #"Z" #"a" - #"z" ".-"]
at-char: #"@"

email: [

   space
   start:
   some mailchar
   at-char
   some mailchar
   end:
   space
   (print copy/part start end)

]


str: "afadfa adfa asdfasdfa fd [asdfas-:-adfadf-:-adfa-adfadfsda-:-com] adfafaf 
a af"

parse/all str [any [email | skip]]

parse [aa zzz cc][some [set w word! (?? w cont: if w = 'zzz [[end 
skip]]) cont]]

Assuming SRC: contains the source text, it seems to work too:

header-char: complement charset "^/:"
EOL2: rejoin [newline newline]
parse/all src [
	some [
		some [pos: #" " (change pos #"-") | header-char]
		#":" pos: newline (change/part pos " {" 1)
		[to EOL2 | to end] pos: (change pos "} ") skip skip
	]
]
probe construct to block! src

Right, i added skiping of useless newline.

parse/all src [
	some [
		any newline
		some [pos: #" " (change pos #"-") | header-char]
		#":" pos: newline (change/part pos " {" 1)
		[to EOL2 | to end] pos: (change pos "} ") skip skip
	]
]

Could you figure it ?

I got it working. I use the following trick - I identify DOMAIN\USER:(RIGHT) 
or (RIGHT) sections first. Then I put weirdly markers around and 
catch the rest with the skip. The file is "clean", so actually what 
do I skip is either spaces, or path. I do check in emit function:

emit: does [
 if find tmp: trim copy/part p-start p-end ":\" [path: tmp]
 print [path domain user rights]
]

;--- rules - spaces, tabs, newlines

spacer-chars: charset [#" " #"^-" #"^/"]
spacers: [some spacer-chars]

;--- user-rights rules
;--- would be easier, if filesystem would not allow () ...

right-char: charset [#"A" - #"Z"]
right-rule: ["(" 1 2 right-char ")" ]

rights-rule: [r-start: some right-rule r-end: (rights: copy/part 
r-start r-end)]

;--- rule to identify user part

user-chars: complement charset {".,;:\/*}
user-rule: [copy user some user-chars ":" ]


;--- rule to identify domain - I expect it being typed in CAPITAL, 
can contain "-"
;--- the exception is "NT AUTHORITY" - contains space

domain-chars: charset [#"A" - #"Z" "-"]
domain-rule: [
    "NT AUTHORITY\" (domain: "NT AUTHORITY")
    |
     copy domain some domain-chars "\"  
]


;--- rules for combinations of: rights only (RIGHT), or DOMAIN\USER:(RIGT)
domain-user-rights: [
     rights-rule 
    |
     domain-rule
     user-rule
     rights-rule
]


parse/all str: read from-file [p-start: any [ p-end: domain-user-rights 
(emit) p-start: | skip ] to end]

just like this fails too. even though we are at the end:

>> print parse "123456789" [9 skip here:] index? here
true
== 10
>> print parse "123456789" [10 skip here:] index? here
false
== 10

In R2:

>> parse/all { X X  XX X X} [(prin 'a) some [(prin 'b) "X" (prin 
'c) [(prin 'd) "X" (prin 'e) | (prin 'f) skip (prin 'g)] (prin 'h) 
| (prin 'i) skip (prin 'j)] (prin 'k)]
abijbcdfghbcdfghbijbcdehbijbcdfghbcdfijbik== true

In R3:

>> parse/all { X X  XX X X} [(prin 'a) some [(prin 'b) "X" (prin 
'c) [(prin 'd) "X" (prin 'e) | (prin 'f) skip (prin 'g)] (prin 'h) 
| (prin 'i) skip (prin 'j)] (prin 'k)]
abijbcdfghbcdfghbijbcdehbijbcdfghbcdfijk== true


In both cases the fij near the end should should be fgh - a bug in 
PARSE.

About STAY, i don't see the interest to continue even if the following 
rule is not matched . Can someone give an use case ?

because when i  do this:

>> parse [1] [stay skip ?? to end]
to: [1]
== true

or

>> parse [ ] [stay skip ?? to end]
to: [ ]
== true

it's like doing:
>> parse [ ...] [?? to end]

STAY have no purpose to my mind...

I would like to say how the new parse is powerfull and light.
For example: 
I have a block which contains 1, 2, or 3 values

I have to insert something between 1 and 2, if there is at least 
2 values.
and something else between 2 and 3., if there is 3 values.

See:

parse block [
	skip
	not end
	insert [ _ ] skip
	not end
	insert [ . ]
]

Is that not marvelous ?

how does skip not end work? I don't get it.

parse block [
	skip   ;** skip the first value

 not end   ;** check if the block have a second value (if not, then 
 stop)

 insert [ _ ] skip   ;** insert what is inside [ ] before the second 
 vlue , skip what it has been inserted, and skip one more time to 
 pass the second value.
	not end  ;** check if there is a third value (if not, then stop)
	insert [ . ]  ;** insert [.] before the third value 
]

What is the advantage?:


1) by not consuming input this would be a direct inversion of the 
rule. Example:

    parse ""a" [not end ...]


is a meaningful rule, and it is quite trivial to see, that any rule 
consuming input would not be a direct inversion of this rule.


NOT SOMETHING actually means, that at the current input position 
the SOMETHING rule shall not match. That does not give us any information, 
that NOT should skip any input (how far should it?).

2) This version of NOT is compatible with PEG

3) It is consistent with the AND operation:

   [AND rule] is equivalent to [NOT [NOT rule]]

Yet another example:


    [NOT skip] is equivalent to the [END] rule and is meaningful only, 
    when NOT does not skip any input

Sunanda, one way:

>> out: clear []

>> parse "this-is-a-string" [mark1: any [thru "-" [to "-" | to end] 
mark2: (append out copy/part mark1 mark2) skip mark1:]]
>> out
== ["this-is" "a-string"]

>> parse [a b c] [(value: none) copy value to 3 skip to end (probe 
value)] 
[a b]
== true


>> parse [a b c] [(value: none) copy value thru 3 skip to end (probe 
value)]
[a b]
== true

>> parse [a b c] [?? copy value thru 1 skip to end]              
            
co? : [a b c]
== true

>> parse [a b c] [?? copy value thru 1 skip to end]              
            
coo:: [a b c]
== true

e.g. 

    parse [a b c] [?? copy value thru 1 skip to end]   

should have preferably been

    parse [a b c] [?? copy value 1 skip to end]

any [and skip copy tmp to end]
any [copy tmp [skip to end]]
etc...

I see your point, but what if the ANY block contains production rules 
?

parse "" [any [and skip copy tmp to end break | insert "1" and insert 
"2"]]

(i know, stupid example)

Hi! Quick question about parsing REBOL code itself... I'm putting 
together an entry for a contest which is line-constrained (no more 
than 250 SLOC), so I want to crush my code down as much as possible 
while still having something that actually looks like code (I know 
about using the compression, but I want something that looks like 
a program).


I'm starting with Carl's REBOL parser from the cookbook, but it seems 
to skip the colons for initializers ("x: x + 1" -> [x x + 1]). Here's 
my current hack of his parser:

tokens: copy []
parse read %contest-entry.r blk-rule: [
    some [
        str:
        newline |

        #";" [thru newline | to end] new: (probe copy/part str new) |
        [#"[" | #"("] (append tokens str/1) blk-rule |
        [#"]" | #")"] (append tokens str/1) break |

        skip (set [value new] load/next str  append tokens :value) :new
    ]
]


Any ideas why it might be skipping the vital ":" character? Thanks 
very much!

Hi! Thanks for taking a look at the code. 


I went over it again, it seems that part of the problem was in the 
fact that the parsed objects weren't transliterated into strings 
as I had expected. I.e. if you look at the output of the code snippet 
above, it seems OK, but examination of the types of the data in the 
tokens array turn up things that don't convert to strings too well 
without help. I've puzzled over Carl's pretty printer, and I _think_ 
I understand why now... 


Either way, I was able to modify it to give me the kind of output 
I wanted. To repay you for your kind attention, I will post my code 
here, but in crushed form, so it doesn't take up too much space... 
; - )


REBOL [ Title: "REBOL Compressor" ] emit-space: func [ pos ] [ append 
out pick

[ #" " "" ] found? not any [ find "[(" last out find ")]" first pos 
] ] emit:

func [ from to ] [ emit-space from word: copy/part from to long: 
( length? out )

+ length? word if 80 < long [ append lines out out: copy "" ] append 
out
copy/part from to ] lines: copy [ ] clean-script: func [
Returns new script text with standard spacing.
 script "Original Script text"

/local str new ] [ out: append clear copy script newline parse script 
blk-rule:

[ some [ str: some [ newline ] ( ) | #";" [ thru newline | to end 
] new: ( ) | [

#"[" | #"(" ] ( emit str 1 ) blk-rule | [ #"]" | #")" ] ( emit str 
1 ) break |

skip ( set [ value new ] load/next str emit str new ) :new ] ] append 
lines out

remove lines/1 print [ length? lines "lines." ] lines ] write/lines 
%crushed.r
clean-script read %c.r print read %crushed.r

Thanks!

set 'use-rule func [

    "Create a recursion and thread-safe parse rule with local variables. 
    R2/R3 compatible."
    words [block!] "Local word(s) to the parse rule"
    rule  [block!] "Parse rule"
] [
    make object! [

        ; Create a new function context. 'Inner-body refers to a function 

        ; with access to CONTEXT-FN's context without being influenced 
        ; directly by the context.
        spec: copy [/local]
        append spec words
        inner-body: func ['word] [inner-inner-body word]
        context-fn: func spec reduce [:inner-body first words]
        

        ; Bind the rule the caller gave us to the new context we just created.
        inner-inner-body: func [word] [bind/copy rule word]
        bound-rule: context-fn
        

        ; Now define the use rule. Because this is an "active" rule,
        ; with state we need to include some state variables used
        ; by the internal PARSE call ('pos and 'success).
        pos: none
        success: none
        inner-inner-body: func [word] [

            ; If the parse of the rule succeeds, we set the parse position

            ; to the where the rule match ended, otherwise we don't change

            ; the parse position and use [end skip] to return a false 
            ; result (for R2 compatibility).
            success: either parse pos [bound-rule pos: to end] [
                [:pos]
            ] [
                [end skip]
            ]
        ]
        set 'rule copy/deep [pos: (context-fn) success]
    ]
    rule
]

set 'use-rule func [

    "Create a recursion and thread-safe parse rule with local variables. 
    R2/R3 compatible."
    words [block!] "Local word(s) to the parse rule"
    rule  [block!] "Parse rule"
] [
    make object! [

        ; Create a new function context. 'Inner-body refers to a function 

        ; with access to CONTEXT-FN's context without being influenced 
        ; directly by the context.
        spec: copy [/local]
        append spec words
        inner-body: func ['word] [inner-inner-body word]
        context-fn: func spec reduce [:inner-body first words]
        

        ; Bind the rule the caller gave us to the new context we just created.
        inner-inner-body: func [word] [bind/copy rule word]
        bound-rule: context-fn
        

        ; Now define the use rule. Because this is an "active" rule,
        ; with state we need to include some state variables used

        ; by the internal PARSE call ('pos and 'success). They are used to 
        ; "transfer" the inner parse state to the "outer parse".
        pos: none
        success: none
        inner-inner-body: func [word] [

            ; If the parse of the rule succeeds, we set the parse position

            ; to the where the rule match ended, otherwise we don't change

            ; the parse position and use [end skip] to return a false 
            ; result (for R2 compatibility).
            success: either parse pos [bound-rule pos: to end] [
                [:pos]
            ] [
                [end skip]
            ]
        ]
        set 'rule copy/deep [pos: (context-fn) success]
    ]
    rule
]

set 'use-rule func [

    "Create a recursion and thread-safe parse rule with local variables. 
    R2/R3 compatible."
    words [block!] "Local word(s) to the parse rule"
    rule  [block!] "Parse rule"
] [
    make object! [

        ; Create a new function context. 'Inner-body refers to a function 

        ; with access to CONTEXT-FN's context without being influenced 
        ; directly by the context.
        spec: copy [/local]
        append spec words
        inner-body: func ['word] [inner-inner-body word]
        context-fn: func spec reduce [:inner-body first words]
        

        ; Bind the rule the caller gave us to the new context we just created.
        inner-inner-body: func [word] [bind/copy rule word]
        bound-rule: context-fn
        

        ; Now define the use rule. Because this is an "active" rule,

        ; with state, we need to include some state variables used

        ; by the internal PARSE call ('pos and 'success). They are used to 
        ; "transfer" the inner parse state to the "outer parse".
        pos: none
        success: none
        inner-inner-body: func [word] [

            ; If the parse of the rule succeeds, we set the parse position

            ; to the point where the rule match ended, otherwise we don't 

            ; change the parse position and use [end skip] to return a false 
            ; result (for R2 compatibility).
            success: either parse pos [bound-rule pos: to end] [
                [:pos]
            ] [
                [end skip]
            ]
        ]
        set 'rule copy/deep [pos: (context-fn) success]
    ]
    rule
]

if you call 'temp a "rebol level variable" in the above example expression, 
how would you call it in the expression below?

(temp: either 1 > 0 [none] [[end skip]]) temp

If you want to fail to an alternate, you can assign the block [end 
skip] to a variable that would normally be set to none, and then 
make references to that variable whenever you want to trigger a failure 
condition.

opt-fail: none

parse "abc" [some [["a" | "b" | (opt-fail: [end skip])] opt-fail]]

in R2,  the best way is to set a word to the value you're evaluating, 
and conditional to that value's pass/fail, you switch the following 
rule to allow it to continue or track back, so it matches another 
rule.


here is a rather verbose example.  note that this can be tweaked 
to be a shorter rule, but it becomes hard to map out how each part 
of the rules relate.. here, each part is clearly layed out.

rebol []


pass-rule: [none]
fail-rule: [thru end]

condition-rule: pass-rule



parse [
	word-a
	"ere"
	835
	word-b
	15
	word
	86
	bullshit
	#doglieru3
	word-c
][
	any [
		
		[
			; this rule only matches words ending with "-?"
			set val word! 
			[
				[
					(
						val: to-string val
						either #"-" = pick (back back tail val) 1  [
							condition-rule: pass-rule
						][
							condition-rule: fail-rule
						]
					)
					condition-rule
					(print ["PATTERN WORD:" val])
				]
				|[
					(print ["Arbitrary word: " val])
				]
			]
		]
		
		| skip
	]
]

ask ""

R3 but obfuscated.

match: [
	  some [thru #"-"] skip end 	(print [w "end with -?"])
	| some [thru #"*"] end		(print [w "end with *"])
]

parse  [
	word-a 	"ere" 	835 	word-b 	15
	word* 	w86	bullshit*	#doglieru3 	word-c
][
	some [
 		  and change set w word! [(form w)]
		  change [do into match | skip] w
		| skip
	]
]

[thru end] is not a good rule to use to fail. A much more reasonable 
rule is [end skip]

Lad   [thru end] means *exactly* the same thing as  [end skip].  
 I don't know why R3 decided to change that, but I find that a regression.

It does not, Max.

[thru end] is supposed to mean:

[end | skip]

, i.e. it fails in R2 only because of the faulty implementation

Err, correcting myself

a: [thru end] is supposed to mean the same as a: [end | skip a]

;BEG propose en new func by Claude 
	remove-all-rows: func[][
		remove/part skip data (length? data) cols
		redraw
	]
	;END

REBOL[]


send: func [
	"Send a message to an address (or block of addresses)"
	;Note - will also be used with REBOL protocol later.
	address [email! block!] "An address or block of addresses"
	message "Text of message. First line is subject."
	/only   "Send only one message to multiple addresses"
	/header "Supply your own custom header"
	header-obj [object!] "The header to use"
	/attach "Attach file, files, or [.. [filename data]]"
	files [file! block!] "The files to attach to the message"
	/subject "Set the subject of the message"
	subj "The subject line"
	/show "Show all recipients in the TO field"
	/local smtp-port boundary make-boundary tmp from
][
	make-boundary: does []

	if file? files [files: reduce [files]] ; make it a block
	if email? address [address: reduce [address]] ; make it a block
	message: either string? message [copy message] [mold message]

	if not header [                 ; Clone system default header
		header-obj: make system/standard/email [

   subject: any [subj copy/part message any [find message newline 50]]
		]
	]
	if subject [header-obj/subject: subj]
	either none? header-obj/from [

  if none? header-obj/from: from: system/user/email [net-error "Email 
  header not set: no from address"]
		if all [string? system/user/name not empty? system/user/name][
			header-obj/from: rejoin [system/user/name " <" from ">"]
		]
	][
		from: header-obj/from
	]
	if none? header-obj/to [
		header-obj/to: tmp: make string! 20
		if show [
			foreach email address [repend tmp [email ", "]]
			clear back back tail tmp
		]
	]
	if none? header-obj/date [header-obj/date: to-idate now]

	if attach [

  boundary: rejoin ["--__REBOL--" system/product "--" system/version 
  "--" checksum form now/precise "__"]
		header-obj/MIME-Version: "1.0"

  header-obj/content-type: join "multipart/mixed; boundary=" [{"} skip 
  boundary 2 {"}]
		message: build-attach-body message files boundary
	]

	;-- Send as an SMTP batch or individually addressed:
	smtp-port: open [scheme: 'esmtp]
	either only [ ; Only one message to multiple addrs
		address: copy address
		; remove non-email values
		remove-each value address [not email? :value]

  message: head insert insert tail net-utils/export header-obj newline 
  message
		insert smtp-port reduce [from address message]
	] [
		foreach addr address [
			if email? addr [
				if not show [insert clear header-obj/to addr]

    tmp: head insert insert tail net-utils/export header-obj newline 
    message
				insert smtp-port reduce [from reduce [addr] tmp]
			]
		]
	]
	close smtp-port
]

resend: func [
	"Relay a message"
	to from message /local smtp-port
][
	smtp-port: open [scheme: 'esmtp]
	insert smtp-port reduce [from reduce [to] message]
	close smtp-port
]

build-attach-body: function [
	{Return an email body with attached files.}
	body [string!] {The message body}

 files [block!] {List of files to send [%file1.r [%file2.r "data"]]}
	boundary [string!] {The boundary divider}
][
	make-mime-header
	break-lines
	file
	val
][
	make-mime-header: func [file] [
		net-utils/export context [

   Content-Type: join {application/octet-stream; name="} [file {"}]
			Content-Transfer-Encoding: "base64"

   Content-Disposition: join {attachment; filename="} [file {"^/}]
		]
	]
	break-lines: func [mesg data /at num] [
		num: any [num 72]
		while [not tail? data] [
			append mesg join copy/part data num #"^/"
			data: skip data num
		]
		mesg
	]
	if not empty? files [
		insert body reduce [boundary "^/Content-type: text/html^/^/"]
		append body "^/^/"
		if not parse files [
			some [
				(file: none)
				[
					set file file! (val: read/binary file)
					| into [
						set file file!
						set val skip ;anything allowed
						to end
					]
				] (
					if file [
						repend body [
							boundary "^/"
							make-mime-header any [find/last/tail file #"/" file]
						]
						val: either any-string? val [val] [mold :val]
						break-lines body enbase val
					]
				)
			]
		] [net-error "Cannot parse file list."]
		append body join boundary "--^/"
	]
	body
]

You should be able to open/direct, skip to the end and write a space 
or null to the end

As for the hash (or assoc) index and list data combo, it has some 
advantages. When you are inserting and removing data a lot lists 
have a known speed benefit but the real advantage as far as indexes 
are concerned is in how lists handle series offsets (I'm using the 
word offset here because I'm using the word index to refer to the 
external hash/assoc index).


Blocks encode their offsets as a number offset from the beginning 
of the series:

>> a: [a b c]
== [a b c]
>> b: skip a 2
== [c]
>> index? b
== 3
>> insert next a 'd
== [b c]
>> b
== [b c]
>> index? b
== 3

List offsets are pointers to the associated list element.

>> a: make list! [a b c]
== make list! [a b c]
>> b: skip a 2
== make list! [c]
>> index? b
== 3
>> insert next a 'd
== make list! [b c]
>> b
== make list! [c]
>> index? b
== 4


If you are indexing your data and your data in in a block, you need 
to update your index with almost every insertion and removal because 
the references to latter positions of the block in the index will 
be invalid. With list insertion and removal, external references 
are likely to still be valid unless the referenced elements themselves 
are deleted. If you are sure to delete the reference from the index 
(or replace it with nones) the rest of the index should be OK. New 
index references can just be tacked on the end, or put into the first 
empty entry. This makes live indexes a lot more practical.


On the down side, if you are using lists and they are long enough 
to make linear searches impractical, you really do need an external 
index for them to be useful. Also you need to balance the overhead 
and complexity of keeping the indexes updated against their benefit. 
This technique is not for the faint of heart unless you can get some 
guru to do algorithms for you.

Not the same thing. If you have skip > length of the series, it will 
only do one iteration and your access to the results off the end 
will usally be none, unless you constrain it yourself. The question 
is whether negative skip should be silently constrained or generate 
an error, as a general rule.

Ladislav, I've tested random some more. The equal sign, =, is used 
to test in the end of RANDOM, if the result should be changed to 
0.0. This will change more values, than if =? was used. I use =? 
in my test. My test goes like this:

REBOL [
	Title:		"Random distribution test"
	Author:		"John Niclasen"
]

random/seed now
dist: clear []	; distribution
tt62: to integer! 2 ** 62
a: tt62 - 1024
loops: 100000
loop loops [
	i: random 1024
	if i > 512 [i: i + a]	; test close to 0.0 and close to 1.0
	y: i - 1 / tt62 * 1.0
	if y =? 1.0 [y: 0.0]	; the result of random 1.0
	y: form y
	either find dist y [
		dist/:y: dist/:y + 1
	][
		repend dist [y 1]
	]
]
while [not tail? dist] [
	dist/1: load dist/1		; change strings back to decimals
	dist: skip dist 2
]
dist: head dist
sort/skip dist 2	; sorting distribution
print dist
mean: 0.0
foreach [value count] dist [
	mean: value * count + mean
]
mean: mean / loops	; calculating the mean value
print mean	; this should be 0.5


The test is testing values close to 0.0 and close to 1.0. Notice 
the high count of 0.0 result compared to other low values. Also notice, 
how the mean value is close to 0.25, where it should be 0.5. Try 
out-comment the change of y to 0.0. Then the result will be much 
better.

Howerver when you don't know what you can put and what you can skip 
you end with a ugly code full of useless things

I came with something existing, and said: Now, how can i do this 
more rebolish...

parse/case opcode [
	any [
		start: 
		| "nn" end: (change/part start get-byte end)
		| "+d" end: (change/part start get-d end)
		| "e" end: (change/part start get-e end)
		| skip
	]
]

--- mod-userdir.r.original	2010-05-09 19:28:10.000000000 +0200
+++ mod-userdir.r	2010-05-11 00:45:24.000000000 +0200
@@ -12,40 +12,81 @@
 	on-started: does [do boot-code]
 	on-reload:  does [clear boot-code]
 	
-	get-ugid: func [name [string!] /local file uid gid][
-		if none? attempt [file: read %/etc/passwd][
+	get-ugid: func [name [string!] /local file line uid gid][
+		unless attempt [file: read/lines %/etc/passwd][
 			log/error "accessing /etc/passwd failed"
 			return none
 		]
-		unless parse/all file [
-			thru name 2 [thru col]
-			copy uid to col skip
-			copy gid to col
-			to end
-		][
-			log/error "reading /etc/passwd failed"
+		foreach line file [
+			if all [line: find/case/match line name  col = first line][
+				return either parse/all next line [
+					thru col
+					copy uid to col skip
+					copy gid to col
+					to end
+				][
+					reduce [to-integer uid to-integer gid]
+				][
+					log/error "invalid format reading /etc/passwd !"
+					none
+				]
+			]
+		]
+		log/error "user not found in /etc/passwd"
+		none
+	]
+	
+	get-gid: func [name [string!] /local file line gid][
+		unless attempt [file: read/lines %/etc/group][
+			log/error "accessing /etc/group failed"
 			return none
 		]
-		reduce [to-integer uid to-integer gid]
+		foreach line file [
+			if all [line: find/case/match line name  col = first line][
+				return either parse/all next line [
+					thru col
+					copy gid to col
+					to end
+				][
+					to-integer gid
+				][
+					log/error "invalid format reading /etc/group !"
+					none
+				]
+			]
+		]
+		log/error "group not found in /etc/group"
+		none
 	]
 	
-	change-id: func [id [word! integer!] /user /group][
-		if word? id [
-			if none? id: get-ugid mold id [return none]
-			id: pick id to-logic user

+	change-id: func [id [string! integer!] /user /group /local gid][
+		either string? id [
+			unless id: get-ugid id [return none]
+			set [id gid] id
+		][
+			gid: id
 		]
-		either user [
+		if group [setgid gid]
+		if user [
 			;logger/file.log: join logger/file ["-" id %.log]
 			setuid id
-		][setgid id]
+		]
+	]
+	
+	change-gid: func [id [string! integer!]][
+		if string? id [
+			unless id: get-gid id [return none]
+		]
+		setgid id
 	]
 	
 	words: [
 		user: [word! | integer!] in globals do [
-			repend boot-code ['change-id/user to-lit-word args/1]

+			repend boot-code either word? args/1 [['change-id/user/group 
mold args/1]] [['change-id/user args/1]]
 		]
 		group: [word! | integer!] in globals do [
-			repend boot-code ['change-id/group to-lit-word args/1]
+			unless empty? boot-code [change boot-code [change-id/user]]

+			insert boot-code reduce ['change-gid either word? args/1 [mold 
args/1][args/1]]
 		]
 	]
 ]
\ No newline at end of file

--- mod-userdir.r.original	2010-05-09 19:28:10.000000000 +0200
+++ mod-userdir.r	2010-05-11 00:45:24.000000000 +0200
@@ -12,40 +12,81 @@
 	on-started: does [do boot-code]
 	on-reload:  does [clear boot-code]
 	
-	get-ugid: func [name [string!] /local file uid gid][
-		if none? attempt [file: read %/etc/passwd][
+	get-ugid: func [name [string!] /local file line uid gid][
+		unless attempt [file: read/lines %/etc/passwd][
 			log/error "accessing /etc/passwd failed"
 			return none
 		]
-		unless parse/all file [
-			thru name 2 [thru col]
-			copy uid to col skip
-			copy gid to col
-			to end
-		][
-			log/error "reading /etc/passwd failed"
+		foreach line file [
+			if all [line: find/case/match line name  col = first line][
+				return either parse/all next line [
+					thru col
+					copy uid to col skip
+					copy gid to col
+					to end
+				][
+					reduce [to-integer uid to-integer gid]
+				][
+					log/error "invalid format reading /etc/passwd !"
+					none
+				]
+			]
+		]
+		log/error "user not found in /etc/passwd"
+		none
+	]
+	
+	get-gid: func [name [string!] /local file line gid][
+		unless attempt [file: read/lines %/etc/group][
+			log/error "accessing /etc/group failed"
 			return none
 		]
-		reduce [to-integer uid to-integer gid]
+		foreach line file [
+			if all [line: find/case/match line name  col = first line][
+				return either parse/all next line [
+					thru col
+					copy gid to col
+					to end
+				][
+					to-integer gid
+				][
+					log/error "invalid format reading /etc/group !"
+					none
+				]
+			]
+		]
+		log/error "group not found in /etc/group"
+		none
 	]
 	
-	change-id: func [id [word! integer!] /user /group][
-		if word? id [
-			if none? id: get-ugid mold id [return none]
-			id: pick id to-logic user

+	change-id: func [id [string! integer!] /user /group /local gid][
+		either string? id [
+			unless id: get-ugid id [return none]
+			set [id gid] id
+		][
+			gid: id
 		]
-		either user [
+		if group [setgid gid]
+		if user [
 			;logger/file.log: join logger/file ["-" id %.log]
 			setuid id
-		][setgid id]
+		]
+	]
+	
+	change-gid: func [id [string! integer!]][
+		if string? id [
+			unless id: get-gid id [return none]
+		]
+		setgid id
 	]
 	
 	words: [
 		user: [word! | integer!] in globals do [
-			repend boot-code ['change-id/user to-lit-word args/1]

+			repend boot-code either word? args/1 [['change-id/user/group 
mold args/1]] [['change-id/user args/1]]
 		]
 		group: [word! | integer!] in globals do [
-			repend boot-code ['change-id/group to-lit-word args/1]
+			unless empty? boot-code [change boot-code [change-id/user]]

+			insert boot-code reduce ['change-gid either word? args/1 [mold 
args/1][args/1]]
 		]
 	]
 ]
\ No newline at end of file

let's try to compare following for R2 vs R3: 


 parse "abc^/def^/ghi^/" [start: any [end: newline (print copy/part 
 start end) start: | skip]]

s: now/time/precise loop 1000000 [parse "abc^/def^/ghi^/" [start: 
any [end: newline start: | skip]]] now/time/precise - s

Three consecutive runs:
R2:
0:00:03.11
0:00:02.941
0:00:03.089

R3:
0:00:01.732
0:00:01.679
0:00:01.724

the above code does not run in R3. Dunno if "end" is forbidden or 
became a keyword, but I get following error, if I don't change end: 
to en:


>> s: now/time/precise loop 1000000 [parse "abc^/def^/ghi^/" [start: 
any [end: n
ewline start: | skip]]] now/time/precise - s
** Script error: PARSE - command cannot be used as variable: end:
** Where: parse loop
** Near: parse {abc
def
ghi
} [start: any [end: newline start: | skip...

This was used with small pieces of XML, rather than entire documents, 
but might be a starting point for you.


xml-get-field: func [input name /local xml-field= data other-name] 
[
	xml-field=: compose/deep [ 
		some [

   (rejoin ["<" name ">"]) copy data to (rejoin ["</" name ">"]) to 
   end
			| skip ;(to paren! [prin '.])
		]
	]
	either parse input xml-field= [data] [none]
]

oops ... the end of the function should be replaced by:

	either into [
		match?
	][
		either paths [
			blk: extract blk 2
			new-line/all blk true
		][
			new-line/skip blk true 2
		]
	]

Got an iterative msort-do for R3:

msort: func [s l /local mid end rest step][
    forskip s 2 [
        unless (compare s/1 s/2) [swap s next s]
    ]
    step: 2
    loop -1 + log-2 l [
        rest: forskip s step * 2 [
            merge s             step 
                  skip s step   step
            s
        ]
        unless empty? end: skip rest step [
            merge rest      step
                  end       length? end
        ]
        step: step * 2
    ]
]

Not fully tested though...sorry

Desiding what to do with block indexes out of range is a tough call, 
I think. I understand the argument not to cause errors, if it can 
be handled somehow, but I'm not sure, handling out-of-range problems 
is always good. What if it's a user bug in the code, that made the 
index get out of range? Then the user won't easily find that bug, 
as it causes no error.


It's not possible to index a block lower than 1 (first element). 
It's only possible to index out of range in the other end of the 
block, getting past the tail. And that can only be done by having 
an index there, and then remove something from earlier in the block. 
When the index is beyond the tail, then it has to be desided what 
to do with
	insert, remove, skip, next, back, pick, select, append
used on that index. (and maybe more like TAIL?, INDEX?, ...)

What does other languages do?

Right.

For blocks, inserting doens't change position of other indexes to 
same series. What I expect, is that the insert is from the index 
given, before the insert is carried out. Like:

>> s: [a b c]
>> insert/only s skip s 2
should result in
	[[c] a b c]

, where the first element is a pointer to one before the end of s, 
not two before the end of s as we have today.

I don't know where the test suite for SPLIT is, but the rule in effect 
for that changed from the old source that Gabriele and I originally 
created. The final rule, for string/char/bitset delimiters was originally 
this:


    [any [mk1: some [mk2: dlm break | skip] (emit copy/part mk1 mk2)]]

but is now this:


    [any [mk1: [to dlm mk2: dlm | to end mk2:] (keep copy/part mk1 mk2)]]


It looks like that changed due to http://issue.cc/r3/573, but obviously 
wasn't run through a test suite. I don't know what caused the issue 
with the above bug, as that parse rule returns a correct result.

The original was written before MAP-EACH and the new COLLECT. Here 
is the source I have, updated to use those as the current version 
does, but with the last rule reverted to the original.

Related cc reports: 
    http://issue.cc/r3/1096
    http://issue.cc/r3/690

split: func [

    "Split a series into pieces; fixed or variable size, fixed number, 
    or at delimiters"
    series	[series!] "The series to split"

    dlm		[block! integer! char! bitset! any-string!] "Split size, delimiter(s), 
    or rule(s)." 

    /into	"If dlm is an integer, split into n pieces, rather than pieces 
    of length n."
    /local size count mk1 mk2
][
    either all [block? dlm  parse dlm [some integer!]] [
            map-each len dlm [
                either positive? len [
                    copy/part series series: skip series len
                ] [
                    series: skip series negate len

                    ; return unset so that nothing is added to output
                    ()
                ]
            ]
    ][
        size: dlm   ; alias for readability
        collect [
            parse/all series case [
                all [integer? size into] [

                    if size < 1 [cause-error 'Script 'invalid-arg size]
                    count: size - 1
                    size: round/down divide length? series size
                    [

                        count [copy series size skip (keep/only series)]
                        copy series to end (keep/only series)
                    ]
                ]
                integer? dlm [

                    if size < 1 [cause-error 'Script 'invalid-arg size]

                    [any [copy series 1 size skip (keep/only series)]]
                ]

                'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                    [any [mk1: some [mk2: dlm break | skip] (keep copy/part mk1 mk2)]]
                ]
            ]
        ] 
    ]
]

split: func [

    "Split a series into pieces; fixed or variable size, fixed number, 
    or at delimiters"
    series	[series!] "The series to split"

    dlm		[block! integer! char! bitset! any-string!] "Split size, delimiter(s), 
    or rule(s)." 

    /into	"If dlm is an integer, split into n pieces, rather than pieces 
    of length n."

    /local size piece-size count mk1 mk2 res fill-val add-fill-val
][
    either all [block? dlm  parse dlm [some integer!]] [
        map-each len dlm [
            either positive? len [
                copy/part series series: skip series len
            ] [
                series: skip series len
                ; return unset so that nothing is added to output
                ()
            ]
        ]
    ][
        size: dlm   ; alias for readability
        res: collect [
            parse/all series case [
                all [integer? size  into] [

                    if size < 1 [cause-error 'Script 'invalid-arg size]
                    count: size - 1

                    piece-size: to integer! round/down divide length? series size
                    if zero? piece-size [piece-size: 1]
                    [

                        count [copy series piece-size skip (keep/only series)]
                        copy series to end (keep/only series)
                    ]
                ]
                integer? dlm [

                    if size < 1 [cause-error 'Script 'invalid-arg size]

                    [any [copy series 1 size skip (keep/only series)]]
                ]

                'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                    [any [mk1: some [mk2: dlm break | skip] (keep/only copy/part mk1 
                    mk2)]]
                ]
            ]
        ]

        ;-- Special processing, to handle cases where the spec'd more items 
        in

        ;   /into than the series contains (so we want to append empty items),

        ;   or where the dlm was a char/string/charset and it was the last 
        char

        ;   (so we want to append an empty field that the above rule misses).
        fill-val: does [copy either any-block? series [[]] [""]]
        add-fill-val: does [append/only res fill-val]
        case [
            all [integer? size  into] [

                ; If the result is too short, i.e., less items than 'size, add
                ; empty items to fill it to 'size.

                ; We loop here, because insert/dup doesn't copy the value inserted.
                if size > length? res [
                    loop (size - length? res) [add-fill-val]
                ]
            ]
            ; integer? dlm [
            ; ]

            'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                ; If the last thing in the series is a delimiter, there is an

                ; implied empty field after it, which we add here.
                case [
                    bitset? dlm [

                        ; ATTEMPT is here because LAST will return NONE for an 

                        ; empty series, and finding none in a bitest is not allowed.

                        if attempt [find dlm last series] [add-fill-val]
                    ]
                    char? dlm [
                        if dlm = last series [add-fill-val]
                    ]
                    string? dlm [
                        if all [
                            find series dlm
                            empty? find/last/tail series dlm
                        ] [add-fill-val]
                    ]
                ]
            ]
        ]
                
        res
    ]
]

split: func [

    "Split a series into pieces; fixed or variable size, fixed number, 
    or at delimiters"
    series	[series!] "The series to split"

    dlm		[block! integer! char! bitset! any-string!] "Split size, delimiter(s), 
    or rule(s)." 

    /into	"If dlm is an integer, split into n pieces, rather than pieces 
    of length n."

    /local size piece-size count mk1 mk2 res fill-val add-fill-val
][
    either all [block? dlm  parse dlm [some integer!]] [
        map-each len dlm [
            either positive? len [
                copy/part series series: skip series len
            ] [
                series: skip series negate len
                ; return unset so that nothing is added to output
                ()
            ]
        ]
    ][
        size: dlm   ; alias for readability
        res: collect [
            parse/all series case [
                all [integer? size  into] [

                    if size < 1 [cause-error 'Script 'invalid-arg size]
                    count: size - 1

                    piece-size: to integer! round/down divide length? series size
                    if zero? piece-size [piece-size: 1]
                    [

                        count [copy series piece-size skip (keep/only series)]
                        copy series to end (keep/only series)
                    ]
                ]
                integer? dlm [

                    if size < 1 [cause-error 'Script 'invalid-arg size]

                    [any [copy series 1 size skip (keep/only series)]]
                ]

                'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                    [any [mk1: some [mk2: dlm break | skip] (keep/only copy/part mk1 
                    mk2)]]
                ]
            ]
        ]

        ;-- Special processing, to handle cases where the spec'd more items 
        in

        ;   /into than the series contains (so we want to append empty items),

        ;   or where the dlm was a char/string/charset and it was the last 
        char

        ;   (so we want to append an empty field that the above rule misses).
        fill-val: does [copy either any-block? series [[]] [""]]
        add-fill-val: does [append/only res fill-val]
        case [
            all [integer? size  into] [

                ; If the result is too short, i.e., less items than 'size, add
                ; empty items to fill it to 'size.

                ; We loop here, because insert/dup doesn't copy the value inserted.
                if size > length? res [
                    loop (size - length? res) [add-fill-val]
                ]
            ]
            ; integer? dlm [
            ; ]

            'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                ; If the last thing in the series is a delimiter, there is an

                ; implied empty field after it, which we add here.
                case [
                    bitset? dlm [

                        ; ATTEMPT is here because LAST will return NONE for an 

                        ; empty series, and finding none in a bitest is not allowed.

                        if attempt [find dlm last series] [add-fill-val]
                    ]
                    char? dlm [
                        if dlm = last series [add-fill-val]
                    ]
                    string? dlm [
                        if all [
                            find series dlm
                            empty? find/last/tail series dlm
                        ] [add-fill-val]
                    ]
                ]
            ]
        ]
                
        res
    ]
]

Well, I just read the code.

You replaced this:

    [any [mk1: some [mk2: dlm break | skip] (emit copy/part mk1 mk2)]]
by this:

    [any [mk1: [to dlm mk2: dlm | to end mk2:] (keep copy/part mk1 mk2)]]


In the first case: the rule is used to extract the matching sequences

In the second case, the rule is used to exclude the matching sequences.

Well it comes down to this: Functions are defined lexically. Though 
they are called dynamically, they aren't called until after they 
have already been bound, definitionally. But as a side effect of 
tasking, those bindings are stack-relative, and those stacks are 
task-local. But random blocks of code outside of functions are bound 
to object contexts, and those are *not* task-local. So that means 
that the old R2 practice of calling shared blocks of code is a really 
bad idea in R3 if any words are modified, unless there is some kind 
of locking or synchronization. This means that those blocks need 
to be moved into functions if their code is meant to be sharable, 
which means that at least as far as RETURN and EXIT are concerned, 
they can be considered lexically scoped. The advantage that we would 
get from being able to call a shared block of code and explicitly 
return in that block is moot, because we can't really do that much 
anymore. This means that we don't lose anything by switching to definitional 
code that we haven't already lost for other reasons. At least as 
far as functions are concerned, all task-safe code is definitional.


Loops are also defined lexically, more or less, and the rebinding 
ones are also task-safe because they are BIND/copy'd to a selfless 
object context that is only used for that one call and thrown away 
afterwards. And most calls to loops are task-safe anyways because 
they are contained in functions. However, the LOOP, FORALL, FORSKIP 
and WHILE loops do not rebind at the moment. We actually prefer to 
use those particular loops sometimes in R3 code because they can 
be more efficient than *EACH and REPEAT, because they don't have 
that BIND/copy overhead. Other times we prefer to use *EACH or REPEAT, 
in case particular loop fits better, or has high-enough repetitions 
and enough word references that the 27% overhead for stack-local 
word reference is enough to be more than the once-per-loop BIND/copy 
overhead. Since you don't have to move blocks into *loops* to make 
them task-safe, you can use blocks referred to by word to hold code 
that would be shared between different bits of code in the same function. 
This is called manual common subexpression elimination (CSE), and 
is a common optimization trick in advanced REBOL code, because we 
have to hand-optimize REBOL using tricks that the compiler would 
do for us if we were using a compiled language. Also, PARSE rules 
are often called from loops, and they are frequently (and in specific 
cases necessarily) referred to by word instead of lexically nested; 
most of the time these rules can be quite large, maximizing BIND/copy 
overhead, so you definitely don't want to put the extensive ones 
in a FOREACH or a closure.

Switching to definitional break would have three real downsides:

* Every loop would need to BIND/copy, every time the loop is called, 
including the loops that we were explicitly using because they *don't* 
BIND/copy.

* Code that is not nested in the main loop block would not be able 
to break from that loop. And code that is nested in the main loop 
would BIND/copy.

* We can in theory catch unwinds, run some recovery code, and send 
them on their way (hopefully only in native code, see #1521). Definitional 
escapes might be hard or impossible to catch in this way, depending 
on how they are implemented, and that would mean that you couldn't 
recover from breaks anymore.


The upside to definitional break would be that you could skip past 
a loop or two if you wanted to, something you currently can't do. 
Another way to accomplish that would be to add /name options to all 
the loop functions, and that wouldn't have the BIND/copy overhead. 
Or to use THROW or THROW/name.


The situation with THROW is similar to that of the non-binding loops, 
but more so, still task-safe because of functions. But CATCH and 
THROW are typically the most useful in two scenarios:

* Escaping through a lot of levels that would catch dynamic breaks 
or returns.

* Premade custom escape functions that might need to enforce specific 
semantics.


Both of these uses can cause a great deal of difficulty if we switched 
to definitional throw. In the first case, the code is often either 
broken into different functions (and thus not nested), or all dumped 
into a very large set of nested code that we wouldn't want to BIND/copy. 
Remember, the more levels we want to throw past, the more code that 
goes into implementing those levels. In the second case definitional 
throw would usually not work at all because the CATCH and the THROW 
would contained in different functions, and the code that calls the 
function wrapping the THROW would not be nested inside the CATCH. 
So you would either need to rebind every bit of code that called 
the THROW, or the definitional THROW would need to be passed to the 
code that wants to call it like a continuation (similar concept). 
Either way would be really awkward.


On the plus side of dynamic (whatever), at least it's easy to catch 
an unwind for debugging, testing or recovery purposes. For that matter, 
the main advantage of using THROW/name as the basic operation that 
developers can use to make custom dynamic escape functions is that 
we can build in a standard way to catch it and that will work for 
every custom escape that is built with it. The end to the arms race 
of break-through and catch.