World: r3wp

example: retry [user-function arg1 arg2 arg3 ...] 5

of course, it could be enhanced by reporting the error instead of 
returning none if it fails more than the given times, and so on.

I was going to apologize to you, Gabriele, a few minutes ago I had 
the sudden realization that your version can indeed handle user-function 
with arguments, as your latest post explains.

Your version really makes rebol shine. Its expressiveness is beyond 
par. Bravo.

Gabriele, just one thing, imagine the following user function: f1: 
func [] [return "f1 body"]

Now: retry f1 4 yields none.

It should return "f1 body", no?

Antoher issue that might be a rebol bug is the use of attempt. Normally 
attempt should return a none  value when an error occurs, but consider 
this.

f2: func [] [ do [1 + "x"]]

>> retry f2 4
** Script Error: Cannot use add on string! value
** Where: f2
** Near: 1 + "x"

That's not what we want.

Again apologies, again my stupidity, all the issues I raised in the 
latest posts are non issues, I made a mistake referencing my functions, 
it should be retry :f1 4, retry :f2 4 (note the colon before the 
function name). and then it behaves as expected. Thanks, Gabriele, 
for this humbling lesson in rebol.

shouldn't poke work on port data if pick does?  Seems strange behavior 
for it not to

i'd actually suggest retry [f1] 4  or   retry [f2] 4   with my code. 
 :f also works but if f takes arguments it would break. so it's cleaner 
to just always use a block.

actually, there is one problem with return, which is if you want 
to do   retry [... return 'something ...]  and have it return from 
the calling function, not retry (like if cond [return 'something]). 
to allow that, you need to add the [throw] func attribute, ie. retry: 
func [[throw] code times] ...

Thanks for the advice, Gabriele, I'll play around with it for a while...

Gabriele, I'm trying to understand in what kind of situation a throw 
is required. f1: func [] [if true [return "something"]] works without 
a throw, for example. Can you provide a concrete example of code 
that requires the throw attribute to 'retry? Thanks!

i'm not sure it is needed or not for retry. it depends on how you 
use it.

f: func [] [
    retry [
        ; do something...
        if cond [return something-else]
        ; ...
    ]
    some-val
]

if you want the return inside retry to return from F and not RETRY, 
then you need [throw].

Thanks, Gabriele, I haven't thought about that.

is the sort block dialect broken ?

b-test: ["xxx" "V" 4 "xxx" "M" 3 "yyy" "Laaaa" 2 "yyy" "Lbbbb" 2 
"yyy" "Kaaaa " 2 "yyy" "Haaaa" 2 "yyy" "Aaaaa" 2]

									print ["init               " mold b-test]

sort/skip/compare b-test 3 [reverse 3 2] 			print ["reverse 3 2  
      " mold b-test]

sort/skip/compare b-test 3 [reverse 3 reverse 2]	print ["reverse 
3 reverse 2" mold b-test]

It seems to use the first reverse 3 but ignore the second comparator. 
Any ideas ?

Joe;  I think you need to pass sort/compare a function! not a block! 
 The function template is [a b] and returns true or false or whether 
to swap.  Something like
sort/compare data func [a b] [a > b]

(Note: the names a and b could be any words but the function is called 
with two arguments).

Never mind my blabbering.  Learned something new today.  :)

Can someone remind me how bind a bunch of words to a different context? 
 I want to use the named colors in a special context.

colors: context [red: 255.0.0 green: 0.255.0 blue: 0.0.255]
reduce bind [red green blue] in colors 'self

I'll give it a go :)

anyone know if REBOL runs on PocketPC?

core used to ...

wince 1.1 ?

I don't know if the CE version does but: http://www.rebol.com/platforms-core.html
 (Note: these are oldies but goodies)

Graham;  To quickly get all the colours, try
rebol []


do-thru http://www.rebol.org/library/scripts/capture.rcapture on 
help tuple! capture off
colors: copy []
parse to block! find get-captured newline [
    some [set col word! (append colors col) word! tuple!]
]

;; This will fail, no context
print disarm try [get first colors]
;; Now bind the words to the REBOL context
bind colors 'red  print get first colors

Joe, did you try "[reverse 3 forward 2]" as your comparator?

Request for opinions;  What would you rather read? 
   var: none
...
   var: either flag [value] [none]
or 
   var: if flag [value]


Assuming var can safely be none or a value but the init may not be 
close to the code.

var: pick [ value ] flag

was I allowed that option??

Certainly, but that would not bounce out at me during a quick grok...perhaps 
with exposure.

var: all [flag value]

I favor EITHER or ALL for this, in general.

I'd go with the 'either or the 'if

Forth does it the pick way to avoid using logic

'all is faster than 'if or 'either ... also more "extensible" in 
that it scales, as in:

	var: all [flag1 flag2 flag3 value]
	var: any [flag1 flag2 flag3 value]

Thanks for the opinions gentlemen.  All over the map of course.  
But Gregg's matters most, so either it is.  :)   And I've found the 
either to be the easier grok when quick scanning, no double think 
required.  This is not in tight code, so readability wins over performance 
concerns.


And just an aside;  all [false false] returning none...kinda sucks. 
  all [none none] returning none, sure; but all [false true] should 
be false, not none.  Or change the help doc to ...and returns NONE 
at the first FALSE or NONE.  Well, it doesn't suck persay, it just 
doesn't behave as the help would suggest.

Oh, now Ashley fills in more of the picture as I was typing.  Seeing 
as I can use either or all, perhaps I'll start getting used to all 
for this idiom. :)

It's like 'if in that regard though.  'if returns none when the condition 
is false...

I guess 'all could be considered "all or nothing".

Yeah, I was just griping about docs.  :)  none is fair return, and 
consistent for all cases, pun intended.

this is spinning my brain:

foreach [a b] [1 2 3 4] [print get load "a"]
** Script error: a has no value

How do I bring "a" under the correct context?