World: r3wp

; the docs say
/part - Limits the search to a given length or position. 

range - The range argument. (must be: number series port) 


; but it is not clear how to pass in that range argument as a 'position' 
let alone a series or port

; the only sign of something going wrong other than an error is that 
the 'end' is simply spit back out at the console, i.e., no error 
but bogus 'result''

; last words of the horse thief on the gallows: 'It has all bin a 
lesson to me'
>> equal? start end  ; false
>> equal? head start head end   ; true

The simple thing to state would be that the 'range' option in question 
is precisly that same series, albeit with the current position shifted 
out further.
>> item: find/part start "this" 24
>> item: find/part start "this" (find start newline)
; range as port ( I have not yet seen this )

>> item: find/part start "this" my-port

; when range is port we must be reading 'start' from a data-source 
( ? )

ditto for copy/part

As Newbie I have to realize that the 'series' mentioned in the HELP 
is that self-same series.

>> t:  copy :end

>> item: find/part start "this" t   ; ERROR  but not at all obvious;

>> item: find/part start "this" "^/    Then test these.^/"  ; ERROR 
  even though true that   >> equal? "^/    Then test these.^/" :end

I would have my tutorial read:
	some series S at some position
	that same series S at some further position

And: think of 'find' as 'try to reposition current index in the series'

Without seeing the source for FIND, I have no idea yet how to explain 
that 'range' must be that very same series.  Chalk it up to lack 
of imagination...

; this now makes sense
>> file: %image.jpg

>> print copy/part file find file "."  ; == "image"   I will focus 
on this example in my tutorial but only AFTER
>> fileName: "image.jpg"
>> print copy/part fileName find fileName "."  ; == "image"

; as a newbie I found this useful ...
>> tt: "this is my test of X which will fix the XY thing"
>> token: find/part tt "X" find tt "is"   ; == none

>> token: find/part tt "X" find tt "thing"   ; == "X which will fix 
the XY thing"

; I did a dif between the functions in VIEW and those in CORE for 
a default install.  What I get is this ( I hope it is useful to have 
al 106  in one place )

 alert  brightness?  caret-to-offset  center-face  choose  clear-face 
  clear-fields  confine  crypt-strength?

 dbug  deflag-face  desktop  dh-compute-key  dh-generate-key  dh-make-key 
  do-events  do-face  do-face-alt  do-thru  

 draw  dsa-generate-key  dsa-make-key  dsa-make-signature  dsa-verify-signature 
  dump-face  dump-pane  edge-size?  

 editor  emailer  exists-thru?  find-key-face  find-window  flag-face 
  flag-face?  flash  focus  get-face  

 get-net-info  get-style  hide  hide-popup  hilight-all  hilight-text 
  hsv-to-rgb  in-window?  inform  

 insert-event-func  inside?  install  launch-thru  layout  link-relative-path 
  load-image  load-stock  

 load-stock-block  load-thru  local-request-file  make-face  notify 
  offset-to-caret  open-events  outside?  

 overlap?  path-thru  read-net  read-thru  remove-event-func  request 
  request-color  request-date  request-dir  

 request-download  request-file  request-list  request-pass  request-text 
  reset-face  resize-face  rgb-to-hsv  

 rsa-encrypt  rsa-generate-key  rsa-make-key  screen-offset?  scroll-drag 
  scroll-face  scroll-para  set-face  

 set-font  set-para  set-style  set-user  show  show-popup  size-text 
  span?  stylize  textinfo  unfocus  

 uninstall  unlight-text  unview  vbug  view  viewed?  win-offset? 
  within?

range can be port only if you are searching a port too - but, not 
100% sure how well that works. i bet it only works on buffered ports 
though.

; this is handy if you are new as am I

>> foreach t (sort/compare datatypes func [a b] [ (form a) < (form 
b)]) [print mold t]

I have nothing on  END!  other than   parse ... to end ]

SYMBOL! is internal houskeeping for names of words (?) and a routine! 
is for working with a call to a DLL  ( of my 54 datatypes in a 2.6.3 
VIEW exec )

Robert  you can get a similar list by doing

? !

or using   "? datatype!"

not as much fun as exploring/learning with your own funcs, but help 
"?" can do some great things, including matching on datatype "? tuple!" 
is a quick way to lookup colours.

Thanks.  And is that colours or colors?  ;-)

; interesting question ... Rebol lets me spell it "colour" if I really 
want to :-)
alias 'color "colour"
view layout [label with [colour: red] "hello"]

Robert;  Make sure you check out  http://www.rebol.it/romano/and 
in particular http://www.rebol.it/romano/#sect1.1.anamonitor 3.0 
and 2.0.  Not something for your average I'm new resident but I have 
a feeling you'll appreciate Romano's utilities.

Here is one of my first encounters with unset!  when working on a 
tutorial to introduce console Rebol to someone who knows Common Lisp
>> m: [1 2 3]
== [1 2 3]
>> m
== [1 2 3]
>> probe m
[1 2 3]
== [1 2 3]
>> print mold m
[1 2 3]
>> mold m
== "[1 2 3]"
>> type? print mold m
[1 2 3]
== unset!
>> type? mold m
== string!
>> type? probe m
[1 2 3]
== block!
>>

the answer is interesting for  me as a newbie and lies in
>> source probe

; the error from trying
>>  n: print mold m
; natually leads to
help print
; and since this fails
p: write %tmp.txt :anything"
; with
help write

; we get to clarify binding words to values, functions, procedures 
 evaluation and returned values

; I hope to get tutorials prepared for OCaml and Scheme as well as 
Haskell and Curl, Perl, Python, Ruby and Smalltalk based on my experience 
as a newbie while I am still a newbie ...

; i.e.,
>> type? write %tmp.txt "newbie"
== unset!
>> unset? write %tmp.txt "new"
== true

both English Rebol books call print and prin 'functions'

The Rebol docs dictionary lumps all the words together as 'functions'

The challenge I have in introducing Rebol in a tutorial is to explain 
why the second expression fails:
>> c: open %temp.txt
>> d: close %temp.txt
; when explaining that the last line seen in
>> source send

; is not an indication that the function named send returns a value. 
 In many languages procedures can be called functions. Is Rebol one 
of them?

; not all mathematicians can add and many cannot teach mathematics 
but can teach naval history. and such.

>> c: open %temp.txt
>> e: insert c "test"
>> close %temp.txt

>> type? e         ; this is easy to explain to Smalltalker as in 
ST you cannot assume that a method returns self

they are all functions, as the all return a value. some return the 
value "unset!" which is treated somewhat specially by the interpreter. 
you cannot set a word to this value unless you use set/any, and you 
cannot get a word that refers to this value unless you use get/any.

unset! is mainly used to catch typos (eg. if you write pint instead 
of print you get an error), and it's used as a return value by functions 
that don't have anything useful to return.

I wil be sure to cover  get/any  and  set/any 
thanks

; using a context there is no problem traversing a path into nested 
blocks. But there is using nexted blocks alone.  Here is my first 
answer to this...
>> t1: [a "one" b "two" c "three"]
== [a "one" b "two" c "three"]
>> t2: [f t1]
== [f t1]
>> t1/b
== "two"
>> t2/f
== t1
>> t2/f/b
** Script Error: Cannot use path on word! value
** Where: halt-view
** Near: t2/f/b
>> pword: func [path 'word /local blk] [
[    return to-path reduce[path :word]]
>> do pword t2/f c
== "three"

; pword is my first pass at a function to traverse nested blocks 
which are not in an object; the alternative appears to be
blk:  get t2/f
aPathDeeper: make path! [ blk c ]
; anyone know anoth path to take?

; the local was a hold-over from an earlier pass at doing this


pword: func [ { navigate one deeper into nested blocks using a path} 
path 'word { must be a valid path refinement} ] [
  return to-path reduce[path :word]]

; simple nested blocks were not the issue
>> t1: [a "one" b "two" c "three" x [f "for"]]
== [a "one" b "two" c "three" x [f "for"]]
>> t1/x
== [f "for"]
>> t1/x/f
== "for"

; I only have the issue if I build t2 to hold some functor and a 
word bound to a block rather than the block, i.e., not
>> t1: [a "one" b "two" c "three" x [f "for"]]
== [a "one" b "two" c "three" x [f "for"]]
>> t2: reduce['functor t1]
== [functor [a "one" b "two" c "three" x [f "for"]]]
>> t2/functor/c
== "three"

t2/functor/x/f  ; also OK of course

; this issue persists 
>> t2: [functor t1]
== [functor t1]
>> p3: to-path reduce[ t2/functor 'x]
== t1/x
>> do p3
== [f "for"]
>> p3: to-path reduce[ t2/functor 'x/f]
== t1/x/f
>> do p3
** Script Error: Invalid path value: x/f
** Where: halt-view
** Near: t1/x/f
; there seems to be no way to "append'" to a path ??

>> p4: to-lit-path [t1 x/f]
== 't1/x/f
>> do p4
** Script Error: Invalid path value: x/f
** Where: halt-view
** Near: t1/x/f
>> t1/x/f
== "for"

; this works
>> p4: to-lit-path 't1/x/f
== 't1/x/f
>> do p4
== "for"

; but it is no help if t am trying to pass in the path the I wish 
to "extend" deeper

>> p4: to-path "t1/x/f"
== t1/x/f
>> do p4
** Script Error: Invalid path value: t1/x/f
** Where: halt-view
** Near: t1/x/f
>> type? p4
== path!
>> get first p4

** Script Error: get expected word argument of type: any-word object 
none
** Where: halt-view
** Near: get first p4

; using get first or get second or get last usually is handy diagnosing 
what is reported as a path but in fact fails as a path

>> p4: to-path 't1/x/f
== t1/x/f
>> get first p4
== [a "one" b "two" c "three" x [f "for"]]

; If I'm understanding this correctly, you are trying to resolve 
a single path to a value in nested blocks (I'll take the liberty 
of reimaging the example):

path: 'language/en/one
language: [en english]
english: [one "one" two "two"]

resolve path ; == "one"

; I'd look at this in two ways -- a) set up the blocks so the path 
works with 'do:

language: reduce ['en english]
resolve: :do

resolve path ; == "one"

; or b) step through the path and resolve each value in turn:

resolve: func [:path [path!] /local wd val][
    wd: first path: copy path remove path val: get wd
    while [all [block? val not tail? path]]
        wd: first path remove path
        val: val/:wd
        if word? val [val: get val]
    ]
    val
]

I am trying to compare what I can do in Rebol to what I can do in 
another language with functors

What hamstrings me is that a path cannot be extended unless the blocks 
are literally nested or in an object

I am hoping some one will da ythat in R3 path! is more like a series!
path: this/thing
path: append path 'what
rez: path

(sorry, missed an opening bracket in 'while)

path: 'this/thing
append path 'what
probe path
probe to-block path

sorry what is a bad choice
make that 'whatever

bind to two valid paths
compose with one word nested in a block
you can append all you want
type? is path
and the path will not be valid

my little pword func was the shortest thing I could build

path: join 'language/en 'one
probe resolve path
path: join 'language/en 'two
probe resolve path