AltME groups: search

Can I vote in r3 to add to-any.. which stops at the first matching 
rules in the order of the block being parsed, as opposed to the order 
in the parse rules  This would make many rules simpler or make parse 
easier to use in Q&D stuff.

i'd actually implement switch using parse. i find it very useful 
to be able to specify multiple values for the same block.

Umm, yes and no on the fear.  Yes fear kept me from holding a lecture 
on the subject, but I usually PARSE from reading the pretty print 
code.  That's how my locate utility works.  But I'm not concerned 
with us.  I'm concerned with construction bosses and non-tech professors 
having access to a programming language and learning maybe one or 
two tricks a week.  I'm also on the side of the gurus in terms of 
correctness and concise coding, but I'd like to see REBOL ,the system, 
that out of the box would be a robust battle tank.


Add taint to the fuel, it would still function; perhaps not gracefully, 
but the big guns would still fire.  Today, the slighest spoonful 
of sugar and our tank dies on the field, no movement, no guns.


foreign! and Steeve's suggestion of scan till whitespace (and yes, 
some source code would load as almost all completely foreign! gibberish 
if a quote was out of place, but so, we can take that and fix it). 
 But at least REBOL wouldn't die; the data/code would be loaded and 
inspectable.  And yes, this could lead to the odd rare catastrophic 
failure, but we get that potential with "clean" datatype! scripts 
too.  I think the slight increased risk is worth the new group of 
users this could attract.

I'd say there is a case for adapting Rebol's vocabulary, eg:


 measure! - proposed a long time ago - 2cm 3.4cl 5o (degrees) 1em 
 - found elsewhere, eg CSS

 date! - recognize some common alternate constructs - 12-Mar-2009T04:00
	money! - the suggested: $1,000.00


I'd love to see Rebol mature along these lines.  The literal types 
are the essense of Rebol's being, they make for expressive problem 
solving and efficient data exchange with some resemblence to terms 
we would use on paper - all with 'load as its core arbiter.  It'd 
be great to be able to extract meaning from any stream of data, and 
I think if any language can, it's Rebol - however, it just seems 
beyond the scope of 'load which has this specifically and valuably 
defined purpose.  Whereas 'parse can be used to describe anything! 
- even if you load junk!, you're still going to need 'parse to make 
sense of it...

parse "12345" [copy a to 2 copy b to 3 copy c to 4 copy d to 5 copy 
e to 6]
== true
>> a
== "1"
>> b
== "2"
>> c
== "3"
>> d
== "4"
>> e
== "5"

You'd probably need parse if the item was more complex.
I think parse would be overkil here.

if that is the struct of the data stored in a file, it should not 
be too hard to parse the file to get the information...looks like 
a 3-D rendering file or ?

Is it possible to set the modification date on a directory?  I keep 
getting errors whereas it works with files in win32.

>> set-modes %xml-parse.r [ modification-date: 1-Jan-2005 ]
>> set-modes %www/ [ modification-date: 1-Jan-2005 ]
** Access Error: Cannot open /D/rebol/rebXR/www/
** Near: set-modes %www/ [modification-date: 1-Jan-2005]
>> set-modes %www [ modification-date: 1-Jan-2005 ]
** Access Error: Cannot open /D/rebol/rebXR/www
** Near: set-modes %www [modification-date: 1-Jan-2005]
>>

mention in...  parse test ...you should replace test with your d 
word.

show: func [ d /local alpha ][ 

	get-city:		[thru "City:" copy city to "^/"]
	get-stateprov:	[thru "Stateprov:" copy stateprov to "^/"]
	get-country:	[thru "country:" copy country to "^/" to end]

	parse d [get-city get-stateprov get-country]

	print [ "City: " a ] 
	print [ "StateProv: " b ]
	print [ "Country: " c ]
]

If you didn't know the order of the data being provided to you then 
you could generalize the code even further... here are the two lines 
that would change....

 get-country:	[thru "country:" copy country to "^/"]		; remove "to 
 end"

 parse d [any [get-city get-stateprov get-country] to end]	; added 
 'any block and "to end"

;here's a working show... but didn't easily come across a solution 
to allow for an unkown order of items to find

show: func [ d /local alpha ][ 

	get-city:	[thru "City:" copy city to "^/"]
	get-stateprov:	[thru "Stateprov:" copy stateprov to "^/"]
	get-country:	[thru "country:" copy country to "^/"]

	parse d [get-city get-stateprov get-country to end]

	print [	"City:" tab trim city newline
		"Stateprov:" tab trim stateprov newline
		"Country:" tab trim country newline
	]
]

tm: func [p act [block!] /local t][t: now/time/precise loop p :act 
print now/time/precise - t]

flat-while: func[b][a: copy b while [not tail? a][a: change/part 
a a/1 1] a: head a]

flat-repeat: func[b][a: copy [] repeat i length? b [insert tail a 
pick b i] a]

flat-parse: func [b][a: copy [] parse b r: [any [ p: block! :p into 
r | skip (insert/only tail a first p)]]a]
flat-load: func[b][load form b]
b1: [[1 2 3 4 5][6 7 8 9 0]]
tm 10000 [flat-while b1]  ;== 0:00:00.062
tm 10000 [flat-repeat b1] ;== 0:00:00.063
tm 10000 [flat-parse b1]  ;== 0:00:00.172
tm 10000 [flat-load b1]   ;== 0:00:00.046

b2: head insert/dup copy [] [a b c d] 300
b3: head insert/dup copy [] b2 100

tm 1000 [flat-while b3]  ;== 0:03:03.985
tm 1000 [flat-repeat b3] ;== 0:02:11.125
tm 1000 [flat-parse b3]  ;== 0:02:43.704
tm 1000 [flat-load b3]   ;== 0:00:52.344

parse-simple-date: func [
	"Parse a string containing a date value; return a date! value."
    date [any-string!]

    /def-day def-d [integer! word!] "Default day for mm/yyyy format. 
    Number or 'last."
    /local dig sep d m y set-def-day tmp-dt
][
    dig: charset [#"0" - #"9"]
    sep: charset " -/."
    set [d m y] none
    set-def-day: does [
        d: any [
            all [integer? def-d  def-d]
            all [
                'last = def-d
                foreach fld [d m y] [set fld to integer! get fld]
                tmp-dt: subtract make date! reduce [1 m + 1 y] 1
                tmp-dt/day
            ]
            1
        ]
    ]
    ; assuming mm/dd/yy or mm/yy format
    ; Do we really want to use PARSE/ALL here?
    either parse/all date [

        [copy m 1 2 dig  sep  copy d 1 2 dig  sep  copy y 1 4 dig]
        | [copy m 1 2 dig  sep  copy y 1 4 dig  (set-def-day)]
    ][
        foreach fld [d m y] [set fld to integer! get fld]
        ; add century if necessary; window from 1926-2025
        if y < 100 [y: add y pick [1900 2000] y > 25]
        ; swap day and month if it makes sense
        if all [m > 12  d <= 12] [set [m d] reduce [d m]]
        make date! reduce [d m y]
    ][none]
]


set 'date-val func [
	"Do everything possible to convert a value to a date."
    date

    /def-day d [integer! word!] "Default day for mm/yyyy format. Number 
    or 'last"
    /local res
] [
    if any-string? date [trim date]
    any [
        all [date? date  date]
        parse-simple-date/def-day date any [d 1]
        attempt [to date! date]
    ]
]

in 98% of cases I agree with what Brian just said about Parse being 
more powerfull than Regexp.  but in those 2% regexp is SO much more 
powerfull, that it still has its place.   now some of you will ask 
me to say when or why, (I know how we as rebolers think and like 
to challenge each other ;-)  but I cannot give an exact example, 
but having had to implement a few complex systems in both, I remember 
a few times in parse when I'd remember how a single char would replace 
2-3 lines of parse "tricks".

I'd suggest something like this:

-- calculations are done in a special function that is passed a string, 
eg
   ans: calc "(a * b) + (c + d)"
-- the 'calc DOes the string, protected by an 'attempt
-- if it succeeds, it passes back the result

-- if not, it throws an error report. If necessary, you can parse 
the original string and try each part of the calculation to find 
the first failure....Recursively via 'calc to drill down nested parentheses 
of course.

**

Two obvious drawbacks to this suggestion:

1. all variables need to be global -- unless you do a lot of other 
work

2. beware side effects of malformed calc strings. You would not like 
it to be "delete/any *.*"

I'd probably use parse, or Gabriele's rewrite function. How did you 
do it?

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

how's this 

>> date: "* 10 May, 2008"
== "* 10 May, 2008"
>> d: parse date none
== ["*" "10" "May" "2008"]
>> remove-each b d [ not any [ parse b alphas parse b digits ] ]
== ["10" "May" "2008"]
>> d: to-block form d
== [10 May 2008]

Gabriele, if we had DO in PARSE we would still need DO/next. Just 
not for nforeach - neither DO/next nor DO in PARSE would be appropriate 
there. Nor would REDUCE be needed. All you'd need would be BIND/copy 
and SET, and some loop function.

That's a nice idea for a sort of "REBOL explainer" application.
But it would be difficult to do in the Library.

The Library does attempt to load and parse scripts -- that's how 
we do the colorisation. But (as with Gabriele's code) we rely on 
REBOL's own reflective abilities to tell us what is a word, function, 
operator etc.

The Library runs an old version of Core (and even if we update that, 
we'd never run a version of View on a webserver) so it does not have 
access to all the information a proper explainer.highlighter would 
need.
Take this script for example:

http://www.rebol.org/cgi-bin/cgiwrap/rebol/view-script.r?color=yes&script=reboldiff.r

'new-line is a valid REBOL word, but it is not colored: that's because 
it is not a word in the version we use.

So sadly, the colorisation at REBOL.or remains a nice bit of eye 
candy rather than a solidly dependable feature.

I realized there was this traversal option using a lit-path! treated 
as a series! but it did not seem to if what I already had was a path! 
 held by a word and I wanted to 'extend' that value with a word.

This arises when the embedded word becomes bound to a different block. 
 In that case an OBJECT! looks to be the only option but then the 
WORDSs in the PATH come already bound to values and so are not 'functors' 
as are 'a 'd and 'e in your example.

I  want to construct a resultant valid path! from a valid path! + 
a lit-word where that word has no value but serves only as functor.

I had hoped that the func to-lit-path would be the answer, but I 
see now that the default Rebol DO path! evaluation precludes this 
kind of 'append'.

I should be able to use a modified version of your eval-path func 
to take as args a valid path! and a word!

My path idea is more like a 'tilde' than our '/' such that I can 
have
        ; blk/key~wrd1~wrd2~wrd3 ... ~wrd-n     ; e.g.,  
    path~wrd1~wrd-i~wrd-j ~wrd-k    ; becomes
; ...
    path2~wrd-m~wrd-n  ;  i.e.,
        ; blk/key/putative-confirmed-key~wrd-m~wrd-n   
PARSE is likely part of the answer if I go that TILDE route.
Once I have a lit-path! your eval-path is the traversal.
A blk of args to a func such as

  construct_dpath: func  [ dpath [lit-path!]  functor-words-blk  [block! 
  ]  /local v1 v2] [ 

should model my case OK and that dpath can be constructed by modified 
versions of your eval-path.  Thanks

== true

>> parse "A.B!C.D." [ any [ [thru  "." | thru  "!" ] mark: (print 
mark ) ] ]
B!C.D.
D.

>> parse "A.B!C.D." [ any [ [thru  "!" | thru  "." ] mark: (print 
mark ) ] ]
C.D.
D.
--- in first case it skips the C in second it skips the B ..

str: "a.b.c.d!e?f. "
chars: complement charset ".!?"
>> parse str [any chars tmp: to end (uppercase tmp)] str
== "a.B.C.D!E?F. "

>> parse str: "assd.asd!d" [any chars tmp: (uppercase tmp)] str
== "assd.ASD!D"

the difference between using a set-word and SET word!:

parse [a b c d] [
	w1: word! (probe w1)
	w2: word! (probe w1 probe w2)
	set w3 word! (probe w1 probe w2 probe w3)
	w4: word! (probew1 probe w2 probe w3 probe w4/1)
]

so you'd just create a block before the parse, and dump the data 
which you want in there, using your new structure.

Maybe these are some variations of what you are looking for


parse/all "fd doixx s x x x oie    x } " [some [copy d   "x" (print 
d) | skip]]


parse/all "fd doixx s x x x oie    x } " [some [copy d 1 2  "x" (print 
d) | skip]]


parse/all "fd doixx s x x x oie    x } " [some [copy d  2  "x" (print 
d) | skip]]


parse/all "fd doixx s x x x oie    x } " [some [copy d   "xx" (print 
d) | skip]]


parse/all "fd doixx s x x x oie    x } " [some [[copy d  "x"  copy 
e  "x" (print [e d]) ] | skip]]


parse/all "fd doixx s x x x oie    x } " [some [ (g: copy "" ) 2 
[copy d  "x"  (append g d)  ]  (print g )  | skip]]

or you are looking for the pairs

 parse/all "fd doixx s x x x oie    x } "  [ some [  [ (g: copy "" 
 ) 2 [ copy d "x"  (append g d ) any notx  | skip  ] (if not empty? 
 g [print g]) ]  ] ]

I forgot notx

notx: complement charset "x"

parse/all "fd doixx s x x x oie    x } "  [ some   [ (g: copy "" 
) 2 [ copy d "x"  (append g d ) any notx  | skip  ] (if not empty? 
g [print g]) ]  ]

this is what I dont expect.

parse/all "fd doixx s x x x oie    x } " [some [copy d   "x" (print 
d) | skip]]

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

regarding 

parse/all "fd doixx s x x x oie    x } " [some [copy d   "x" (print 
d) | skip]]
what did you expect?

If you know what you are looking for you can extend it to


parse/all "fd doixx s x x x oie    x } " [some [copy d   ["x"   | 
"y" | "z" ]    (print d) | skip]]
and you will get your searched values.

But maybe I just don't understand the problem.

Right, I would say that the following snippit is the most educational 
thing I have done with PARSE.  It shows me a lot of things about 
what is happening & validates the construction and use of charsets 
& whatever the 'address block is called.     Thanks everyone for 
your help.

digit: charset [#"0" - #"9"]
address: [1 3 digit "." 1 3 digit "." 1 3 digit "." 1 3 digit]

a: does [prin 'a] b: does [prin 'b] c: does [prin 'c] d: does [prin 
'd] e: does [prin 'e] f: does [prin 'f]
parse/all {1 23 4.5.6.12 222.1.1.1 7 8} [some[

 (a) copy x address (prin x) some[ (b) copy y address break | skip 
 (c)] (print y) | skip (d)
]]
adadadadada4.5.6.12bcb222.1.1.1

I'm also working on very similar to your case right now. I don't 
know if its useful for you but here how I do (on Windows)


command: {csvde -u -f export.ldap -d "ou=myou" -r "(objectClass=user)" 
-s 10.1.31.2 -a "" "" -l "DN,sn,uid,l,givenName,telephoneNumber,mail"}

call/wait/console/shell/error command %export.err  ;export all users, 
bind annonymous

if 0 < get in info? %export.err 'size [print "error" editor %export.err 
halt]
lines: read/lines %export.ldap

;create an object from the first line (field names, order may differ 
from what you give in the batch)

ldap-object: construct append map-each v parse first content none 
[to-set-word v] 'none
foreach line lines [
	(
		set words-of o: make ldap-object []  parse/all line {,}
		append users: [] o
	)
] ;append all valid users as an object to a block
probe users

I hope it gives some idea.

1.2.57
>> parse/all {"a""b""c"de} "e"
== ["a" "b" "c" "d"]
Please, add the bug to RAMBO.

Graham,  I'd probably use parse/all rather than parse. Also don't 
forget the parse-header function and all the associated bug fixing 
work related to it in view 1.3 project. May or may not be of use 
to you.

parse/all data [any [to "*" a: skip b: to "*" c: skip d: :a (change/part 
a rejoin ["<strong>" copy/part b c "</strong>"] d)] to end]

markup-chars: charset "*~"
non-markup: complement markup-chars
tag1: ["*" "<strong>" "~" "<i>"]
tag2: ["*" "</strong>" "~" "</i>"]
parse/all data [
    any non-markup
    any [

        ["*" a: skip b: to "*" c: skip d: | "~" a: skip b: to "~" c: skip 
        d: ] :a (
            change/part a rejoin [
                select tag1 copy/part a b
                copy/part b c
                select tag2 copy/part c d
            ] d
        ) any non-markup
    ]
    to end
]

Here's a simplified version of my example that can handle multiple 
instances of multiple markup types and be adapted to different end 
tags (thanks Tomc for the idea!):

markup-chars: charset "*~"
non-markup: complement markup-chars
tag1: ["*" "<strong>" "~" "<i>"]
tag2: ["*" "</strong>" "~" "</i>"]
parse/all data [
    any non-markup
    any [

        ; This next block can be generated if you have many markup types...

        [a: copy b "*" copy c to "*" copy d "*" e: | a: copy b "~" copy c 
        to "~" copy d "~" e: ]
        :a (change/part a rejoin [tag1/:b c tag2/:d] e)
        any non-markup
    ]
    to end
]

Here's what I have right now:

		markup-chars: charset "*_@"
		non-markup: complement markup-chars
		inline-tags: [
			"*" "strong"
			"_" "em"
			"@" "code"
		]

		markup-rule: [
			any non-markup
			any [
				[ a: "*" b: to "*" c: skip d: |
				  a: "_" b: to "_" c: skip d: | 
				  a: "@" b: to "@" c: skip d: ] :a (
					change/part a rejoin [ 
						"<" select inline-tags copy/part a b ">"
						copy/part b c 
						"</" select inline-tags copy/part a b ">"
					] d
				) any non-markup
			]
			to end
		]
		parse text markup-rule

okay, here's a slightly tweaked version that uses a multichar markup 
tag:

        markup-chars: charset "[*_-:---]"
        non-markup: complement markup-chars
        inline-tags: [
            "*" "strong"
            "_" "em"
            "@" "code"
            "--" "small"
        ]

        markup-rule: [
            any non-markup
            any [
                [ a: "*" b: to "*" c: skip d: |
                  a: "_" b: to "_" c: skip d: | 
                  a: "@" b: to "@" c: skip d: |
                  a: "--" b: to "--" c: skip skip d: ] :a (
                    change/part a rejoin [ 
                        "<" select inline-tags copy/part a b ">"
                        copy/part b c 
                        "</" select inline-tags copy/part a b ">"
                    ] d
                ) any non-markup | skip
            ]
            to end
        ]
        parse/all text markup-rule

I just found out that I can't do the following:
s: "a b c"
s: "a c b"
parse s ["a" to ["b" | "c"] to end]


The two strings should only symbolize that b and c can alternate. 
But 'to and 'thru don't work with subrules. It's not even stated 
in the documentation that it should but wouldn't it be natural ? 
Or am I missing some complication for the parser if it would support 
this (in the general case indefinite look-ahead necessary for the 
parser - is this the problem?) ? How are other people doing things 
like this - what if you want to parse something like "a bla bla bla 
c" or "a bla bla bla d" if you are interested in the "bla bla bla" 
which might be arbitrary text and thus can't be put into rules ?

I used to parse HL7 messages differently ... splitting them  into 
fields as well.  But this time I thought I 'd try a rule based approach.

It'd be fun to compare parse and REs.....

Maybe a shootout between experts in both.   Both sides could learn 
a lot.

but the true is, that in CSV is logical to have: parse {,d ,d} {,} 
== ["" "d" "d"]

and parse {,"a b, d"  ,d} {,} == ["" "a b, d" "d"]  (so probably 
Carl has true;-)

II was sure I'd posted this just after Oldes' message.....But it 
ain't there now.....Maybe it's in the wrong group)
Andrew has a nice starter set:

http://www.rebol.org/cgi-bin/cgiwrap/rebol/view-script.r?script=common-parse-values.r

And I know he has extended that list extensively to include things 
like email address and URL

I'm a bit stuck because this parse stop after the first iteration. 
 Can anyone give me a hint as to why it stops after one line.

Here is some code:

data: read to-file Readfile

print length? data
224921


d: parse/all data [thru QuoteStr copy Note to QuoteStr thru QuoteStr 
thru quotestr

    copy Category to QuoteStr thru QuoteStr thru quotestr copy Flag to 
    QuoteStr
    thru newline (print index? data)]
1
== false


Data contains hundreds of "memos" in a csv file with three fields: 

 Memo, Category and Flag ("0"|"1")  all fileds are enclosed in quotes 
 and separated by commas.
  

It would be real simple if the Memo field didn't contain double quoted 
words; then 
parse data none
would even work; but alas many memos contain other "words".
It would even be simple if the memos didn't contain commas, then
parse data "," or parse/all data ","
would work; but alas many memos contain commas in the body.

if QuoteStr = "\"", then this looks like it to me:
Note
, "Category", "Flag" 
Note
, "Category", "Flag"

But you don't have a loop or anything - try this:
d: parse/all data [
   some [

      thru QuoteStr copy Note to QuoteStr thru QuoteStr thru quotestr

      copy Category to QuoteStr thru QuoteStr thru quotestr copy Flag to 
      QuoteStr
      thru newline (print index? data)
   ]
]

This change in the parse looks like it works:

>> data: {"Note", "Category", "Flag"
{    "Note", "Category", "Flag"
{    "Note", "Category", "Flag"
{    "Note", "Category", "Flag"
{    }
== {"Note", "Category", "Flag"
Note
, "Category", "Flag"
Note
, "Category", "Flag"
Note
, "Category", "Flag"
}
>> QuoteStr: to-char 34
== #"^""
>> d: parse/all data [
[    some [

[        X: thru QuoteStr copy Note to QuoteStr thru QuoteStr thru 
quotestr

[        copy Category to QuoteStr thru QuoteStr thru quotestr copy 
Flag to QuoteStr
[        thru newline (print index? :X)
[        ]
[    ]
1
29
57
85
== true

maybe this will help:

x: [1 2 3 4 5] parse x [any [x: set d number! (probe x probe d x: 
next x) :x]]

that is what I meant... I'd like parse to do it for us .

and actually... i'd call parse directly in that case ;)

I'm pondering attempting a PARSE lecture here on Altme;  It'd be 
run twice, 9am EST, 9pm EST (or somesuch)  Topic would be dialecting. 
 I want to see if it would work, but I'm no where near a professor 
level rebol.  So, think of it as a kindergarten lecture, as a trial.


Plan;  Post this message - see if there is feedback.  Allow for some 
Q&A time for specific topics of interest.  A week or two later, run 
a hour (probably less) of monologue (interruptions allowed for stuff 
that is just plain wrong ... but other than that participants would 
be asked to hold off on questions).  Followed immediately with a 
Q&A, complaint, correction session.  Then a DocBase page created 
with a merged transcript of the two timezoned lectures, things learned 
and hopefully something along the lines of a simple file management 
(or some such) dialect source code file.  R2 related - for me the 
R3 DELECT still hasn't sunk in.  If it works, then perhaps it could 
become a semi-regular activity...there is going to be a lot to discuss 
come "link to the rebol.dll" time.

I have a question on the above parse by Oldes on Feb 8th.  
If you feed in a [a b c d e f] you will get a-b-c-==false

How can you change the parse so that it will put a dash in between 
all characters, without defining each character?

Patrick, in answer to your first question:
parse [a b c d e f] [
    set x word! (prin form x)
    any [set x word! (prin join "-" form x)]
]

A long time ago, I offered to try a lecture.  Don't feel worthy. 
 So I thought I'd throw out a few (mis)understandings and have them 
corrected to build up a level of comfort that I wouldn't be leading 
a group of high potential rebols down a garden path.


So; one of the critical mistakes in PARSE can be remembered as  "so 
many", or a butchery of some [ any [ , so many.

some asks for a truth among alternatives and any say's "yep, got 
zero of the thing I was looking for", but doesn't consume anything. 
 SOME says, great and then asks for a truth.  ANY say "yep, got zero 
of the thing I was looking for", and still doesn't move, ready to 
answer yes to every question SOME can ask.  An infinite PARSE loop.


Aside: to protect against infinite loops always start a fresh PARSE 
block with [()   the "immediate block" of the paren! will allow for 
a keyboard escape, and not the more drastic Ctrl-C.


So, I'd like to ask the audience; what other PARSE command sequences 
can cause infinite loops?


end?  and is it only  "end", "to end" but "thru end" will alleviate 
that one?  end end end end being true?

>> parse "" [some [() end end end]]
(escape)
>> parse "" [some [() thru end end end]]
== false
>> parse "" [some [() to end end end]]
(escape)
>> 


Ok, but thru end is false.  Is there an idiom to avoid looping on 
end, but still being true on the first hit?

Other trip ups?

term: [word! | into term]
parse [a b [c]] [some term]  ;== true
parse [a b [c d]] [some term]  ;== false

terms: [some [word! | into terms]]
parse [a b [c d]] terms  ;== true

Peter's example, from the blog:
parse [a b c d] [
    any [
      start (acc: 0)
      |
      set inc integer! (acc: acc + inc)
      |
      end
    ]
  ]

My suggested improvement to parse would be a trace (or debug) refinement:
    trace-output-word: copy [] 
    parse/trace string rules trace-output-word 

I'm not entirely sure how it would work. That would depend in part 
on how parse works internally, and so what trace points are possible. 
But, as a minimum, I'd expect it to show me each rule that triggers 
a match, and the current position of the string being parsed.
 parse would  append trace info to the trace-output word


Otherwise, parse is too big a black box for any one other than very 
patient experts.

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
]

I am the editor of the PARSE proposals.


It was decided that I perform this role because Carl is focused on 
the GUI work right now and someone qualified had to do it. With Carl 
busy and Ladislav not here, I am the one left who has the most background 
in parsing and the most understanding of what can be done efficiently 
and what can't. When the PARSE REPs of old were discussed, I was 
right there in the conversation and the originator of about half 
of them, mostly based on my experience with other parsers and parser 
generators. Because of this I am well aware of the original motivation 
behind them, and have had many years to think them through. It's 
just head start, really.


I am also the author of the current implementation of COLLECT and 
KEEP, based on Gabriele's original idea, which was a really great 
idea. It is also really limited. Collecting information and building 
data structures out of it is the basic function that programming 
languages do, and something that REBOL is really good at. I am not 
in any way denigrating the importance of building data structures. 
I certainly did not mean to imply that your appreciation of that 
important task was in any way less important.


The role of an editor is not just to collect proposals, but to make 
sure they fit with the overall goal of the project. This sometimes 
means rejecting proposals, or reshaping them. This is not a role 
that I am sorry about - someone has to do it to make our tool better. 
We are not Perl, this is not anything goes, we actually try to make 
the best decisions here. I hate to seem the bad guy sometimes, but 
someone has to do it :(


PARSE is a portion of REBOL that is dedicated to a particular role. 
It recognizes patterns in data, extracts some of the data, and then 
calls out to the DO dialect to do something with the data. It doesn't 
really do anything to the data itself - everything happens in the 
DO dialect code in the parens. It is fairly simple really, and from 
carefully designed simplicity it gets a heck of a lot of power and 
speed. That is its strength.


The thing that a lot of people don't remember when making improvements 
to a dialect like PARSE is that PARSE is only one part of REBOL. 
If something doesn't go into PARSE, it can go into another part of 
REBOL. We have to consider the language as a whole when we are doing 
things like this.

Here is the overall rationale for the PARSE dialect proposals:

- All new features need to be simple to explain and use, and fast 
at runtime.
- A good feature would be one of these:

  - An extremely powerful enhancement of PARSE's language recognition.

  - A fix to a design flaw in an existing feature, or a compatibility 
  fix.

  - A serious improvement to a sufficiently common use case, or common 
  error.


The reason I didn't want to put COLLECT and KEEP into PARSE is because 
it is a small part of a much bigger problem that really needs a lot 
of flexibility. Different structure collection and building situations 
require different behavior. It just so happens that the DO dialect 
is much better suited to solving this particular problem than the 
PARSE dialect is. Remember, PARSE is a native dialect, and as such 
is rather fixed.


There are some PARSE proposals that make parse actually do something 
with the data itself: CHANGE, INSERT and REMOVE. We were very careful 
when we designed those proposals. In particular, we wanted to provide 
the bare minimum that would be necessary to handle some very common 
idioms that are usually done wrong, even by the best PARSE programmers. 
Sometimes we add stuff into REBOL that is just there to solve a commonly 
messed up problem, so that a well debugged solution would be there 
for people to choose instead of trying to solve it again themselves, 
badly. (This is why the MOVE function got added to R3 and 2.7.6, 
btw.) Even with that justification those features might not make 
it into PARSE because they change the role of PARSE from recognition 
to modification. I have high hopes, though.


Another proposal that might not make it into PARSE is RETURN. RETURN 
is another ease-of-use addition. In particular, the thing it makes 
easy is stopping the parse in the middle to return some recognized 
information. However, it changes the return characteristics of PARSE 
in ways that may have unpredictable results, and may not have enough 
benefit. The proposal that has a better chance of making it is BREAK/return, 
though I'd like to see both (we can hope, right?).


Most of the REPs from Gabriele's doc have been covered. Most of them 
have been changed because we have had time in the last several years 
to give them some thought; the only unchanged ones are NOT and FAIL, 
so far. Some have been rejected because they just weren't going to 
work at all (8 and 12). THROW and DO are still under discussion - 
the proposals won't work as is, but the ideas behind them have merit. 
The rest have been debated and changed into good proposals. Note 
that the DO proposal would be rejected outright for R2, but R3's 
changes to word binding make it possible to make it safe (as figured 
out during a conversation with Anton this evening).


There are other features that are not really changes to the PARSE 
dialect, and so are out of scope for these proposals. That doesn't 
mean that they won't be implemented, just that they are a separate 
subject. That includes delimiter parsing (sorry, Petr), tracing (sorry, 
Henrik), REBOL language syntax (sorry, Graham), and port parsing 
(sorry, Steeve, Anton, Doc, Tomc, et al). If it makes you feel better, 
while discussing the subject with Anton here I figured out a way 
to do port parsing with the R3 port model (it wouldn't work with 
the R2 port model). I will bring these all up with Carl when it comes 
to that.


I hope that this makes the situation and my position on the subject 
clearer. I'm sorry for any misunderstandings that arose during this 
process.

I have run out of ideas, and am asking for more. Through discussions 
with Carl I have a pretty good idea about what would be rejected, 
and what has already been rejected. If you want to make more suggestions, 
please review the proposals that have been made already in the Parse 
Proposals wiki and Gabriele's REPs. If your suggestion is covered 
by something suggested in one of those places you can be sure that 
they have already been debated to death. If not, I'd love to hear 
it :)

Just some ideas for possible usage.


[[item1 item2 | item2 item1 SWAP] ]   ; Put previous two matched 
items in order.
==> [item1 item2]  ; Always sorted.


[ROT [a b c d e]] ;  Rotate items matched by next subrule, if it 
matches. 
==> [b c d e a]  ; 


[start: a [b c] DUP start]  ; Duplicate items from start to current 
parse index.
==>  [a b c a b c]


[a DROP [b c]] ; If next subrule matches, then remove items matched, 
and set parse index back to the beginning of the remove.
==>  [a]

(DROP is just like REMOVE, so not really needed, I think. Just doing 
the exercise to see.)

The above can be categorized by how they fetch their arguments:
- Take two previously matched items/subrules (like SWAP).
- Match the next subrule (like ROT, DROP).
- Use a variable to take the parse index (like DUP).

Your example with alternates (and bug fixes, still ignoring leap 
years):


 m31: ["Jan" | "Mar" | "May" | "Jul" | "Aug" | "Oct" | "Dec"]  ; joins 
 were in wrong direction
	m30: join m31 [| "Apr" | "Jun" | "Sep" | "Nov"]
	m28: join m30 [| "Feb"]

 b28: next repeat x 28 [repend [] ['| form x]]  ; next to skip leading 
 |, numbers don't work in string parsing
	b30: ["29" | "30"]  ; optimization based on above reversed joins
	b31: ["31"]
	parse date-str [
		b28 "-" m28
		| b30 "-" m30
		| b31 "-" m31
	]

The above with CHECK instead:

	m31: ["Jan" "Mar" "May" "Jul" "Aug" "Oct" "Dec"]
	m30: join m31 ["Apr" "Jun" "Sep" "Nov"]
	m28: join m30 ["Feb"]
	b28: repeat x 28 [append [] form x]  ; not assuming 
	b30: ["29" "30"]  ; optimization based on above reversed joins
	b31: ["31"]
	parse date-str [
		copy d some digit "-" copy m some alpha
		check (	any [
			all [find b31 d  find m31 m]
			all [find b30 d  find m30 m]
			all [find b28 d  find m28 m]
		])
	]

Which would be faster would depend on the data and scenario.

Here's a simpler date checker with CHECK:


parse date-str [copy d [1 2 digit "-" 3 alpha "-" 4 digit] check 
(attempt [to-date d])]

'append would do it...

numbers don't work in string parsing

 - I thought about this when I developed the example, thought it might 
 be possible as the numbers appear outside the dialect.  But 'check 
 seems like the better option.  

joins were in the wrong direction
 - d'oh!

simpler date checker

 - that's only useful if to-date recognizes the date format : )  (and 
 using dates was illustrative - there are other situations with similar 
 needs).  Though on dates, what would be the most succinct way with 
 the proposals on the table to do the following?

	ameridate: "2/15/2008"
	parse ameridate ...rule...
	newdate = 15-Feb-2008

One attempt:

	parse ameridate [
		use [d m][
			change [copy m 1 2 digit "/" copy d 1 2 digit]
			(rejoin [d "/" m])
		]
		"/" 4 digit end check (newdate: to-date ameridate)
	]

the last problem I had and steeve and oldes propsoed solutions... 
I got steeve's one but I don't get what "complement charset" in olde's 
does.. >>str: "a.b.c.d!e?f. " chars: complement charset ".!?" >> 
parse str [any chars tmp: to end (uppercase tmp)] str == "a.B.C.D!E?F. 
"<<

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]]

>> 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...
>>

it took me about 30 seconds to solve it with lines.  with a single 
parse rule, after 15m  I was still trying to corner a simple detail 
that meant rewriting the whole rules, or adding a new rule, just 
for one specific situation.  Had I started with another rule setup, 
I'd encountered another nagging situation (like yours has tumbled 
upon).


my time / hour is worth more than 2 milliseconds my of my computer 
consuming 1/4 watt of electricity.  Using 500 bytes more of ram that 
is recycled, also isn't worth consideration.

like I said, I'm pragmatic, that's all there is to it.

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.

Hi All,  I'm new to PARSE, so I've come here to learn a little more. 
 I'm working on and off on a little testing project of my own for 
R3.

My goal is to navigate through some website(s), capture Rebol code, 
and the expeceted responses such as this page: 
http://rebol.com/r3/docs/functions/try.html

I'd like to capture the text inside a block like this:
[ "cmd" {if error? try [1 + "x"] [print "Did not work."]}
rsp
   {Did not work.} 
cmd
  {if error? try [load "$10,20,30"] [print "No good"]}
rsp
  {No good}]


Can anyone point me to some parse example code which can "tear apart" 
an HTTP page based on text and the type of text?

I realize I may be biting off a bit more than I can chew, but I'd 
still like to give it a try.
Thanks in advance.

I put a note up because of my silly misunderstanding of the intent 
of adding AND to PARSE.  But I get odd results with the likes of 
   parse "abeabd" [and [thru "e"] [thru "d'"]]  which behaves like 
ANY

I am still guessing at what is intended in R3-a84 but the first looks 
OK and the second looks like a bug                               
                                                                 
  >> parse "abad"  [thru "a" stay [to "b"] (print "at b") thru "d"]
at b
== true


>> parse "abad"  [stay thru "c" (print "at c")  [to "b"] thru "d"]
at c
== true    ;   BUT must still be a bug

>> parse d: "abc" [change skip 123]
>> d
== "123bc"

It's not necessarily a PARSE limitation, but there are things we'd 
like PARSE to do that aren't always reasonable. :-)


TO and THRU can work very well, but that doesn't mean they'll work 
for every situation. You may have to use rules where you check for 
your target value or just SKIP, marking locations in the input as 
you go.

I want to extract all the dates ( dd-mmm-yy, dd mmm yyyy d mmmmmmm 
yy )


extract-dates: func [ txt 
	/local months dates days month year
][
	dates: copy []
	months: copy []
	digit: charset [ #"0" - #"9" ]
	digits: [ some digit ]
	foreach mon system/locale/months [
		repend months [ mon '|  copy/part mon 3 '| ]
	]
	remove back tail months
	parse txt [
		some [
			to 1 2 digits copy days 1 2 digit [ #" " | #"-" ]
			copy month months
			[ #" " | #"-" ]
			copy year [ 4 digits | 2 digits ]
			( repend dates rejoin [ days "-" month "-" year ] ) |
			thru 1 2 digits ??
		]
	]
	dates
]


extract-dates "asdf sdfsf  11 Jan 2008 12-January-10 fasdfsaf asdf 
as 11 2 3 3  13-Feb-08 asdfasf "

Ok, continuing the discussion from "Performance" group, I'd like 
to ask for some help with parsing rebol format files.

Basically, I'd like to be able to extract a block near the beginning 
or end of a file, while minimizing disk access.

The files to be parsed could be large, so I don't want to load the 
entire contents, but chunks at a time.

So my parse rule should be able to detect when the input has been 
exhausted and ask for another chunk.

(When extracting a block near the end of a file, I'll have to parse 
in reverse, but I'll try to implement that later.)

Using LOAD/NEXT, I still have to use a O(n^2) algorithm. I'd now 
like to do my own parse, which can be O(n).

Question on StackOverflow.....there must be a better answer than 
mine, and I'd suspect it involves PARSE (better answers usually do:)

    http://stackoverflow.com/questions/4093714/is-there-finer-granularity-than-load-next-for-reading-structured-data

>> parse [a b c/d/e] [2 word! into [3 word!]]
== true

Requesting Opinions.  Being a crusty old forther, I really really 
miss the immersive nature of the block editor environment.  Coding 
in forth meant never leaving forth.  Editor, debugger, disk drivers 
etc... all forth commands.  No need to ever have the brain exit forth 
mode.  Now that Rebol is my language of the future, I kinda pine 
for the past.  The wonder and beauty of Rebol keeps being interrupted 
by decisions on what to use to edit that last little bit of script. 
 Notepad, Crimson Editor, Rebol editor? A small annoyance but it 
still disrupts the brain from getting to streaming mode.  So now 
to the question.  My first crack at a forth block editor dialect 
failed miserably.  Dialects need to be LOADable for parse to function. 
 Editing source code makes for unloadable situations.  Do I just 
give up on it and learn to live in the third millenium?  Write a 
utility that doesn't use dialects (which seems to unRebol the solution)? 
 I thought I'd ask you guys, just in case there is a light shining 
in front of me that I can't see.  Thanks in advance.

I'm rethinking the behaviour of my 'import dialect (library: http://bit.ly/rebimport
) when working with structured data. At it's simplest form, 'import 
filters a block of key-string pairs based on a supplied set of constraints: 
import [a "1"][a: integer! is more-than 0] == [a 1] ; or none if 
the constraints are not met


There are two nested forms I'd like to support: 1) a continuation 
of key-value blocks [a [b "1"]] and 2) a block of values [c ["b" 
"1" "foo"]]


The first could just be a recursive function or parse call. The second 
needs a little more thought - on the face of it, it could just verify 
the contents conform to a preset group: [ ["a" "b"] contains some 
of ["a" "b" "c"] ] (or any of), which'd be fine for validating web 
form input (eg. multi-select list), but would rule out, say, a JSON 
block containing objects (as key-value pairs).  I'm trying to figure 
out if this is overkill or a genuinely useful way of validating structured 
data...


Then there's ["1" "2" "3"] <- be nice to validate as [some integer!] 
or [some integer! | decimal!]. I don't want it to be overly complex, 
but it should at least be useful - anyone have any conventional cases 
for validating a block of strings?

n: 100'000
bench: func [code] [t1: now/precise loop n code
	print [difference now/precise t1 mold code]
]
bench [switch 'f [a [] b [] c [] d [] e [] f [] g [] h []]]

bench [parse [f] ['a () | 'b () | 'c () | 'd () | 'f () | 'g () | 
'h ()]]

REBOL []

load-include: func [include [any-block!]][

    either parse inlcude reduce [to-issue 'include file!][load include/2][include]
]

RebGUI: context [
	d: "D"
	ctx: do bind load-include [#include %include.r] 'self
]

RebGUI/ctx/b
RebGUI/ctx/c

Carl has talked several times about a binary format for saving REBOL 
structures (can't find any references off-hand).

That would probably solve this problem as what is saved is, in effect. 
the internal in-memory format: useless for non-REBOL data exchange 
and perhaps dangerous for cross-REBOL releases data exchange, but 
much much faster as it'd avoid most of the parse and load that REBOL 
does now.

You can do some structural pattern matching with parse rules, but 
with how parse is currently implemented it can be a little awkward. 
The lack of arguments to parse rules make recursion quite difficult, 
and the lack of local variables make the rules difficult to use concurrently. 
It is difficult to examine both the data type and the value of elements 
in block parsing, to switch to string parsing mode for string elements, 
to parse lists, hashes or parens, to direct the parse flow based 
on semantic criteria (which is needed to work around any of these 
other problems).


And don't even get me started on the difficulties of structure rebuilding. 
The thing that is the most difficult to do in parse is the easiest 
thing to do with regexes: Search and replace. Didn't we make a web 
site years ago collecting suggestions for improving parse? Wasn't 
a replace operation one of those suggestions? What happened with 
that?


Structural pattern matching and rebuilding currently has to be done 
with a mix of parse and REBOL code that is tricky to write and debug. 
If parse doesn't get improved, I'd rather use a nice declarative 
dialect, preferably with before and after structures, and have the 
dialect processor generate the parse and REBOL code for me. If that 
dialect is powerful enough to be written in itself then we'll really 
be cooking.

REBOL [
	Title:		"SVG Demo"
	Owner:		"Ashley G. Trüter"
	Version:	0.0.1
	Date:		21-Jun-2005
	Purpose:	"Loads and displays a resizeable SVG file."
	History: {
		0.0.1	Initial release
	}
	Notes: {
		Tested on very simple SVG icons
		Only a few basic styles / attributes / commands supported

  Does not handle sizes in units other than pixels (e.g. pt, in, cm, 
  mm, etc)

  SVG path has an optional close command, "z" ... AGG shape equivalent 
  auto-closes

  load-svg function needs to be totally refactored / optimized ... 
  *sample only*
	}
]

;	The following commands are available for path data:
;
;		M = moveto
;		L = lineto
;		H = horizontal lineto
;		V = vertical lineto
;		C = curveto
;		S = smooth curveto
;		Q = quadratic Belzier curve
;		T = smooth quadratic Belzier curveto
;		A = elliptical Arc
;		Z = closepath

;print: none	; comment out this line to enable debug messages

load-svg: function [svg-file [file! string!] size [pair!]] [

 id defs x y to-color to-byte draw-blk append-style svg-size scale-x 
 scale-y
][
	xml: either string? svg-file [parse-xml svg-file] [

  unless %.svg = suffix? svg-file [to error! "File has an invalid suffix!"]
		parse-xml read svg-file
	]

 unless xml/3/1/1 = "svg" [to error! "Could not find SVG header!"]

 ;unless find ["id" "xmlns"] xml/3/1/2/1 [to error! "Could not find 
 ID header!"]

 ;unless xml/3/1/3/1/1 = "defs" [to error! "Could not find DEFS header!"]

	id: xml/3/1/2
	defs: xml/3/1/3


	;
	;	--- Parse SVG id
	;

	svg-size: either find ["32pt" "48pt" "72pt"] select id "width" [
		switch select id "width" [
			"72pt"	[120x120]
			"48pt"	[80x80]
			"32pt"	[60x60]
		]
	][

  as-pair to integer! any [select id "width" "100"] to integer! any 
  [select id "height" "100"]
	]

	x: to integer! any [select id "x" "0"]
	y: to integer! any [select id "y" "0"]

	scale-x: size/x / svg-size/x
	scale-y: size/y / svg-size/y

	;
	;	--- Helper functions
	;


 to-color: func [s [string!]] [	; converts a string in the form "#FFFFFF" 
 to a 4-byte tuple
		to tuple! load rejoin ["#{" next s "00}"]
	]


 to-byte: func [s [string!]] [	; converts a string with a value 0-1 
 to an inverted byte
		255 - to integer! 255 * to decimal! s
	]

	;
	;	--- Parse SVG defs
	;

	draw-blk: copy []

	append-style: function [
		command [string!] blk [block!]
	][
		x xy pen-color fill-color line-width mode size radius shape
		closed? matrix transf-command
	][
		xy: 0x0
		size: 0x0
		line-width: 1
		matrice: make block! []
		radius: none
		transf-command: none
		
		
		foreach [attr val] blk [
			switch attr [
				"transform" [print "tranform have been found" 
						;probe val halt 
						val: parse val "(),"
						transf-command: first val
						probe transf-command
						switch transf-command [
							"matrix" [ 
								foreach word val [
									if not find word "matrix"
									[ 
										insert tail matrice to-decimal word
									]
								]
							
							]
						]
				]
				"style" [
					foreach [attr val] parse val ":;" [
						switch/default attr [
						
							"font-size" [ ]
							"stroke" [
								switch/default first val [
									#"#" [pen-color: to-color val]
									#"n" [pen-color: none]
								][
									print ["Unknown stroke:" val]
								]
							]
							"stroke-width" [line-width: to decimal! val]
							"fill" [
								fill-color: switch/default first val [
									#"#" [to-color val]
									#"n" [none]
								][
									print ["Unknown fill value:" val]
									none
								]
							]
							"fill-rule" [
								mode: switch/default val [
									"evenodd"	['even-odd]
								][
									print ["Unknown fill-rule value:" val]
									none
								]
							]

       "stroke-opacity" [pen-color: any [pen-color 0.0.0.0] pen-color/4: 
       to-byte val]

       "fill-opacity" [fill-color: any [fill-color 0.0.0.0] fill-color/4: 
       to-byte val]
							"stroke-linejoin" [
								insert tail draw-blk switch/default val [
									"miter"		[compose [line-join miter]]
									"round"		[compose [line-join round]]
									"bevel"		[compose [line-join bevel]]
								][
									print ["Unknown stroke-linejoin value:" val]
									none
								]
							]
							"stroke-linecap" [
								insert tail draw-blk 'line-cap
								insert tail draw-blk to word! val
							]
						][
							print ["Unknown style:" attr]
						]
					]
				]
				"x"			[xy/x: scale-x * val]
				"y"			[xy/y: scale-y * val]
				"width"		[size/x: scale-x * val]
				"height"	[size/y: scale-y * val]
				"rx"		[print "rx"]
				"ry"		[radius: to decimal! val]
				"d"	[
					shape: copy []
					x: none
					closed?: false
					foreach token load val [
						switch/default token [
							M	[insert tail shape 'move]
							C	[insert tail shape 'curve]
							L	[insert tail shape 'line]
							z	[closed?: true]
						][

       unless number? token [print ["Unknown path command:" token]]

       either x [insert tail shape as-pair x scale-y * token x: none] [x: 
       scale-x * token]
						]
					]
				]
			]
		]
		insert tail draw-blk compose [
			pen (pen-color)
			fill-pen (fill-color)
			fill-rule (mode)
			line-width (line-width * min scale-x scale-y)
		]
		switch command [
			"rect" [
				insert tail draw-blk compose [box (xy) (xy + size)]
				if radius [insert tail draw-blk radius]
			]
			"path" [
				unless closed? [print "Path closed"]
				either transf-command <> none  [
					switch transf-command [

      "matrix" [insert tail draw-blk compose/only [ (to-word transf-command) 
      (matrice) shape (shape) reset-matrix]]
					]
				][
					insert tail draw-blk compose/only [shape (shape)]
			 	]
				]

   "g" [ print "Write here how to handle G insertion to Draw block" 

    insert tail draw-blk probe compose/only [reset-matrix (to-word transf-command) 
    (matrice)]
				
				]
			]
	]	
  
	probe defs
	foreach blk defs [
		switch first blk [
			"rect"	[append-style first blk second blk]
			"path"	[append-style first blk second blk]
			"g"		[
						print "key word" probe first blk  
						print "matrix and style in G" probe second blk  
						append-style first blk second blk 
						;print "what to draw in G" probe third blk
						foreach blk2 third blk [
							probe blk2
							switch first blk2[ 
								"path" [append-style first blk2 second blk2]
							]
						]
					]
		]
	]
	
	
probe draw-blk
	draw-blk
]

view make face [
	offset:	100x100
	size:	200x200
	action:	request-file/filter/only "*.svg"
	text:	rejoin ["SVG Demo [" last split-path action "]"]
	data:	read action
	color:	white
	effect:	compose/only [draw (load-svg data size)]
	edge: font: para: none
	feel: make feel [
		detect: func [face event] [
			if event/type = 'resize [
				insert clear face/effect/draw load-svg face/data face/size
				show face
			]
			if event/type = 'close [quit]
		]
	]
	options: [resize]
]

REBOL [
	Title:		"SVG Demo"
	Owner:		"Ashley G. Trüter"
	Version:	0.0.1
	Date:		21-Jun-2005
	Purpose:	"Loads and displays a resizeable SVG file."
	History: {
		0.0.1	Initial release
	}
	Notes: {
		Tested on very simple SVG icons
		Only a few basic styles / attributes / commands supported

  Does not handle sizes in units other than pixels (e.g. pt, in, cm, 
  mm, etc)

  SVG path has an optional close command, "z" ... AGG shape equivalent 
  auto-closes

  load-svg function needs to be totally refactored / optimized ... 
  *sample only*
	}
]

;	The following commands are available for path data:
;
;		M = moveto
;		L = lineto
;		H = horizontal lineto
;		V = vertical lineto
;		C = curveto
;		S = smooth curveto
;		Q = quadratic Belzier curve
;		T = smooth quadratic Belzier curveto
;		A = elliptical Arc
;		Z = closepath

;print: none	; comment out this line to enable debug messages

load-svg: function [svg-file [file! string!] size [pair!]] [

 id defs x y to-color to-byte draw-blk append-style svg-size scale-x 
 scale-y
][
	xml: either string? svg-file [parse-xml svg-file] [

  unless %.svg = suffix? svg-file [to error! "File has an invalid suffix!"]
		parse-xml read svg-file
	]

 unless xml/3/1/1 = "svg" [to error! "Could not find SVG header!"]

 ;unless find ["id" "xmlns"] xml/3/1/2/1 [to error! "Could not find 
 ID header!"]

 ;unless xml/3/1/3/1/1 = "defs" [to error! "Could not find DEFS header!"]

	id: xml/3/1/2
	defs: xml/3/1/3


	;
	;	--- Parse SVG id
	;

	svg-size: either find ["32pt" "48pt" "72pt"] select id "width" [
		switch select id "width" [
			"72pt"	[120x120]
			"48pt"	[80x80]
			"32pt"	[60x60]
		]
	][

  as-pair to integer! any [select id "width" "100"] to integer! any 
  [select id "height" "100"]
	]

	x: to integer! any [select id "x" "0"]
	y: to integer! any [select id "y" "0"]

	scale-x: size/x / svg-size/x
	scale-y: size/y / svg-size/y

	;
	;	--- Helper functions
	;


 to-color: func [s [string!]] [	; converts a string in the form "#FFFFFF" 
 to a 4-byte tuple
		to tuple! load rejoin ["#{" next s "00}"]
	]


 to-byte: func [s [string!]] [	; converts a string with a value 0-1 
 to an inverted byte
		255 - to integer! 255 * to decimal! s
	]

	;
	;	--- Parse SVG defs
	;

	draw-blk: copy []

	append-style: function [
		command [string!] blk [block!]
	][
		x xy pen-color fill-color line-width mode size radius shape
		closed? matrix transf-command
	][
		xy: 0x0
		size: 0x0
		line-width: 1
		matrice: make block! []
		radius: none
		transf-command: none
		
		
		foreach [attr val] blk [
			switch attr [
				"transform" [print "tranform have been found" 
						;probe val halt 
						val: parse val "(),"
						transf-command: first val
						probe transf-command
						switch transf-command [
							"matrix" [ 
								foreach word val [
									if not find word "matrix"
									[ 
										insert tail matrice to-decimal word
									]
								]
							
							]
						]
				]
				"style" [
					foreach [attr val] parse val ":;" [
						switch/default attr [
						
							"font-size" [ ]
							"stroke" [
								switch/default first val [
									#"#" [pen-color: to-color val]
									#"n" [pen-color: none]
								][
									print ["Unknown stroke:" val]
								]
							]
							"stroke-width" [line-width: to decimal! val]
							"fill" [
								fill-color: switch/default first val [
									#"#" [to-color val]
									#"n" [none]
								][
									print ["Unknown fill value:" val]
									none
								]
							]
							"fill-rule" [
								mode: switch/default val [
									"evenodd"	['even-odd]
								][
									print ["Unknown fill-rule value:" val]
									none
								]
							]

       "stroke-opacity" [pen-color: any [pen-color 0.0.0.0] pen-color/4: 
       to-byte val]

       "fill-opacity" [fill-color: any [fill-color 0.0.0.0] fill-color/4: 
       to-byte val]
							"stroke-linejoin" [
								insert tail draw-blk switch/default val [
									"miter"		[compose [line-join miter]]
									"round"		[compose [line-join round]]
									"bevel"		[compose [line-join bevel]]
								][
									print ["Unknown stroke-linejoin value:" val]
									none
								]
							]
							"stroke-linecap" [
								insert tail draw-blk 'line-cap
								insert tail draw-blk to word! val
							]
						][
							print ["Unknown style:" attr]
						]
					]
				]
				"x"			[xy/x: scale-x * val]
				"y"			[xy/y: scale-y * val]
				"width"		[size/x: scale-x * val]
				"height"	[size/y: scale-y * val]
				"rx"		[print "rx"]
				"ry"		[radius: to decimal! val]
				"d"	[
					shape: copy []
					x: none
					closed?: false
					foreach token load val [
						switch/default token [
							M	[insert tail shape 'move]
							C	[insert tail shape 'curve]
							S   [insert tail shape 'curv]
							L	[insert tail shape 'line]
							Q   [insert tail shape 'qcurve]
							T   [insert tail shape 'qcurv]
							z	[closed?: true]
							H   [insert tail shape 'hline]
							V   [insert tail shape 'vline]
							A   [insert tail shape 'arc]
						][

       unless number? token [print ["Unknown path command:" token]]

       either x [insert tail shape as-pair x scale-y * token x: none] [x: 
       scale-x * token]
						]
					]
				]
			]
		]
		insert tail draw-blk compose [
			pen (pen-color)
			fill-pen (fill-color)
			fill-rule (mode)
			line-width (line-width * min scale-x scale-y)
		]
		switch command [
			"rect" [
				insert tail draw-blk compose [box (xy) (xy + size)]
				if radius [insert tail draw-blk radius]
			]
			"path" [
				unless closed? [print "Path closed"]
				either transf-command <> none  [
					switch transf-command [

      "matrix" [insert tail draw-blk compose/only [ (to-word transf-command) 
      (matrice) shape (shape) reset-matrix]]
					]
				][
					insert tail draw-blk compose/only [shape (shape)]
			 	]
				]

   "g" [ print "Write here how to handle G insertion to Draw block" 

    insert tail draw-blk probe compose/only [reset-matrix (to-word transf-command) 
    (matrice)]
				
				]
			]
	]	
  
	probe defs
	foreach blk defs [
		switch first blk [
			"rect"	[append-style first blk second blk]
			"path"	[append-style first blk second blk]
			"g"		[
						print "key word" probe first blk  
						print "matrix and style in G" probe second blk  
						append-style first blk second blk 
						;print "what to draw in G" probe third blk
						foreach blk2 third blk [
							probe blk2
							switch first blk2[ 
								"path" [append-style first blk2 second blk2]
							]
						]
					]
		]
	]
	
	
probe draw-blk
	draw-blk
]

view make face [
	offset:	100x100
	size:	200x200
	action:	request-file/filter/only "*.svg"
	text:	rejoin ["SVG Demo [" last split-path action "]"]
	data:	read action
	color:	white
	effect:	compose/only [draw (load-svg data size)]
	edge: font: para: none
	feel: make feel [
		detect: func [face event] [
			if event/type = 'resize [
				insert clear face/effect/draw load-svg face/data face/size
				show face
			]
			if event/type = 'close [quit]
		]
	]
	options: [resize]
]

REBOL [
	Title:		"SVG Demo"
	Owner:		"Ashley G. Trüter"
	Version:	0.0.1
	Date:		21-Jun-2005
	Purpose:	"Loads and displays a resizeable SVG file."
	History: {
		0.0.1	Initial release
	}
	Notes: {
		Tested on very simple SVG icons
		Only a few basic styles / attributes / commands supported

  Does not handle sizes in units other than pixels (e.g. pt, in, cm, 
  mm, etc)

  SVG path has an optional close command, "z" ... AGG shape equivalent 
  auto-closes

  load-svg function needs to be totally refactored / optimized ... 
  *sample only*
	}
]

;	The following commands are available for path data:
;
;		M = moveto
;		L = lineto
;		H = horizontal lineto
;		V = vertical lineto
;		C = curveto
;		S = smooth curveto
;		Q = quadratic Belzier curve
;		T = smooth quadratic Belzier curveto
;		A = elliptical Arc
;		Z = closepath

;print: none	; comment out this line to enable debug messages

load-svg: function [svg-file [file! string!] size [pair!]] [

 id defs x y to-color to-byte draw-blk append-style svg-size scale-x 
 scale-y
][
	xml: either string? svg-file [parse-xml svg-file] [

  unless %.svg = suffix? svg-file [to error! "File has an invalid suffix!"]
		parse-xml read svg-file
	]

 unless xml/3/1/1 = "svg" [to error! "Could not find SVG header!"]

 ;unless find ["id" "xmlns"] xml/3/1/2/1 [to error! "Could not find 
 ID header!"]

 ;unless xml/3/1/3/1/1 = "defs" [to error! "Could not find DEFS header!"]

	id: xml/3/1/2
	defs: xml/3/1/3


	;
	;	--- Parse SVG id
	;

	svg-size: either find ["32pt" "48pt" "72pt"] select id "width" [
		switch select id "width" [
			"72pt"	[120x120]
			"48pt"	[80x80]
			"32pt"	[60x60]
		]
	][

  as-pair to integer! any [select id "width" "100"] to integer! any 
  [select id "height" "100"]
	]

	x: to integer! any [select id "x" "0"]
	y: to integer! any [select id "y" "0"]

	scale-x: size/x / svg-size/x
	scale-y: size/y / svg-size/y

	;
	;	--- Helper functions
	;


 to-color: func [s [string!]] [	; converts a string in the form "#FFFFFF" 
 to a 4-byte tuple
		to tuple! load rejoin ["#{" next s "00}"]
	]


 to-byte: func [s [string!]] [	; converts a string with a value 0-1 
 to an inverted byte
		255 - to integer! 255 * to decimal! s
	]

	;
	;	--- Parse SVG defs
	;

	draw-blk: copy []

	append-style: function [
		command [string!] blk [block!]
	][
		x xy pen-color fill-color line-width mode size radius shape
		closed? matrix transf-command
	][
		xy: 0x0
		size: 0x0
		line-width: 1
		matrice: make block! []
		radius: none
		transf-command: none
		
		
		foreach [attr val] blk [
			switch attr [
				"transform" [print "tranform have been found" 
						;probe val halt 
						val: parse val "(),"
						transf-command: first val
						probe transf-command
						switch transf-command [
							"matrix" [ 
								foreach word val [
									if not find word "matrix"
									[ 
										insert tail matrice to-decimal word
									]
								]
							
							]
						]
				]
				"style" [
					foreach [attr val] parse val ":;" [
						switch/default attr [
						
							"font-size" [ ]
							"stroke" [
								switch/default first val [
									#"#" [pen-color: to-color val]
									#"n" [pen-color: none]
								][
									print ["Unknown stroke:" val]
								]
							]
							"stroke-width" [line-width: to decimal! val]
							"fill" [
								fill-color: switch/default first val [
									#"#" [to-color val]
									#"n" [none]
								][
									print ["Unknown fill value:" val]
									none
								]
							]
							"fill-rule" [
								mode: switch/default val [
									"evenodd"	['even-odd]
								][
									print ["Unknown fill-rule value:" val]
									none
								]
							]

       "stroke-opacity" [pen-color: any [pen-color 0.0.0.0] pen-color/4: 
       to-byte val]

       "fill-opacity" [fill-color: any [fill-color 0.0.0.0] fill-color/4: 
       to-byte val]
							"stroke-linejoin" [
								insert tail draw-blk switch/default val [
									"miter"		[compose [line-join miter]]
									"round"		[compose [line-join round]]
									"bevel"		[compose [line-join bevel]]
								][
									print ["Unknown stroke-linejoin value:" val]
									none
								]
							]
							"stroke-linecap" [
								insert tail draw-blk 'line-cap
								insert tail draw-blk to word! val
							]
						][
							print ["Unknown style:" attr]
						]
					]
				]
				"x"			[xy/x: scale-x * val]
				"y"			[xy/y: scale-y * val]
				"width"		[size/x: scale-x * val]
				"height"	[size/y: scale-y * val]
				"rx"		[print "rx"]
				"ry"		[radius: to decimal! val]
				"d"	[
					shape: copy []
					x: none
					closed?: false
					if all [x not number? token] [

          insert tail shape x * either token = 'V [scale-y][scale-x]
  						    x: none
					]
					foreach token load val [
						switch/default token [
							M	[insert tail shape 'move]
							C	[insert tail shape 'curve]
							S   [insert tail shape 'curv]
							L	[insert tail shape 'line]
							Q   [insert tail shape 'qcurve]
							T   [insert tail shape 'qcurv]
							z	[closed?: true]
							H   [insert tail shape 'hline]
							V   [insert tail shape 'vline]
							A   [insert tail shape 'arc]
						][

       unless number? token [print ["Unknown path command:" token]]

       either x [insert tail shape as-pair x scale-y * token x: none] [x: 
       scale-x * token]
						]
					]
				]
			]
		]
		insert tail draw-blk compose [
			pen (pen-color)
			fill-pen (fill-color)
			fill-rule (mode)
			line-width (line-width * min scale-x scale-y)
		]
		switch command [
			"rect" [
				insert tail draw-blk compose [box (xy) (xy + size)]
				if radius [insert tail draw-blk radius]
			]
			"path" [
				unless closed? [print "Path closed"]
				either transf-command <> none  [
					switch transf-command [

      "matrix" [insert tail draw-blk compose/only [ (to-word transf-command) 
      (matrice) shape (shape) reset-matrix]]
					]
				][
					insert tail draw-blk compose/only [shape (shape)]
			 	]
				]

   "g" [ print "Write here how to handle G insertion to Draw block" 

    insert tail draw-blk probe compose/only [reset-matrix (to-word transf-command) 
    (matrice)]
				
				]
			]
	]	
  
	probe defs
	foreach blk defs [
		switch first blk [
			"rect"	[append-style first blk second blk]
			"path"	[append-style first blk second blk]
			"g"		[
						print "key word" probe first blk  
						print "matrix and style in G" probe second blk  
						append-style first blk second blk 
						;print "what to draw in G" probe third blk
						foreach blk2 third blk [
							probe blk2
							switch first blk2[ 
								"path" [append-style first blk2 second blk2]
							]
						]
					]
		]
	]
	
	
probe draw-blk
	draw-blk
]

view make face [
	offset:	100x100
	size:	200x200
	action:	request-file/filter/only "*.svg"
	text:	rejoin ["SVG Demo [" last split-path action "]"]
	data:	read action
	color:	white
	effect:	compose/only [draw (load-svg data size)]
	edge: font: para: none
	feel: make feel [
		detect: func [face event] [
			if event/type = 'resize [
				insert clear face/effect/draw load-svg face/data face/size
				show face
			]
			if event/type = 'close [quit]
		]
	]
	options: [resize]
]

You could trivially change the parser in Topaz to allow [ and ] inside 
words, and then write something like:

   a[b c]d


but, is that a good thing? So, what's the actual purpose of allowing 
a,b to be a word? So far, the only purpose has been "to parse other 
languages as if they were REBOL". That's not a good purpose, because 
they are *not* REBOL. If you need to parse other syntax, you need 
string parsing. block parsing is for REBOL dialects.


The only sensible reason I can imagine for , to be a word would be 
to use it as an operator so that:

    a , b

means

   also a b


but that has the same readability problems of using . as a "end of 
command marker" in dialects. a nice idea in abstract, but terrible 
in practice.

I can just take it as a game, and land some easy punches on places 
you exposed up-there :)

for example, you mention drawing the lines:
- I prefer consistency
easier parser
- consistend languages are often easier to parse 
various cases where it might look wierd
- f (a.b + c'd)  ~ is this better? this is valid now :)

allowing

- I like languages where creator makes a conceptually focused, clear, 
expandable, consistent "engine" and we can grow and combine that 
beyond what language maker was able to initially imagine.


This Guy (:)) talks about something like this: http://video.google.com/videoplay?docid=-8860158196198824415


REBOL is one of very few languages where this actually is possible, 
another language like this is Factor.


You ask if this could be a word a[ . And in Factor this is the case, 
and they also found a concrete use for this specific case. It's been 
more than year so I have to check where I have seen it. (Factor has 
compilation stage (live compilation too) so they have compile time 
macros where they can extend syntax in various ways).

easier parser: adding , does not make the parser easier. It would 
probably be trivial to allow it *inside* a word, ie. "a,b", but it's 
going to be more complicated to handle , alone and then worry about 
its usage within numbers.


f (a.b + c'd) - that will either immediately look weird to anyone 
used to other languages, or be easily seen as passing one argument. 
f (a,b + c,d) would instead be read as f (a) (b + c) (d) which it 
is not. This is a weak argument in the sense that people knowing 
REBOL will probably have little problem with this... but REBOL is 
"weird" enough already. :)


expandable: right, indeed you have string parsing, and you can do 
whatever you want with it. do you expect other languages to parse 
whatever is thrown at them? no they don't. you have to write the 
parser.


having anything in words: it remains to be proven whether this makes 
things better or worse. i suspect "worse".

Traditional with embedded SQL, the technique is to use "host variables" 
which start with a colon:

 sql reduce “select * from table where [all [col1 = :var1 col2 = :var2 
 ]]”
And you'd magically replace :var1 with the value of var1.


Which is almost exactly the behaviour you'd expect from :var1 in 
REBOL too.

If you insist that that host variables always have a space before 
and after, that makes the whole substitution process a fairly simple 
parse operation.

having more time, i'd just study the binary file format and parse 
it myself. i don't see any show-stopper.