[REBOL] Re: Rolling your own ideal looper: does Repeat still have a bug?
From: g:santilli:tiscalinet:it at: 26-Aug-2000 14:41
Hello [galtbarber--MailAndNews--com]!
On 26-Ago-00, you wrote:
g> See attached rebol file and output.
How about:
>> ideal-looper: func [
[ 'element [word!]
[ 'index [word!]
[ series [series!]
[ code [block!]
[ /local f
[ ] [
[ f: func reduce [element index] code
[ repeat i length? series [f series/:i i]
[ ]
>> ideal-looper char pos "hello" [print [pos char]]
1 h
2 e
3 l
4 l
5 o
Much simpler, isn't it? :-) You get a new context and the correct
bindings for free creating a function.
However, there really seems to be some problems with recursion and
REPEAT:
>> ideal-looper char pos s: "hello" [
[ prin [pos char]
[ ideal-looper char pos s [prin " " prin char]
[ prin newline
[ ]
1 h h e l l o
6 none h e l l o
6 none h e l l o
6 none h e l l o
6 none h e l l o
But:
>> repeat i 10 [prin i repeat i 10 [prin " " prin i] prin newline]
1 1 2 3 4 5 6 7 8 9 10
2 1 2 3 4 5 6 7 8 9 10
3 1 2 3 4 5 6 7 8 9 10
4 1 2 3 4 5 6 7 8 9 10
5 1 2 3 4 5 6 7 8 9 10
6 1 2 3 4 5 6 7 8 9 10
7 1 2 3 4 5 6 7 8 9 10
8 1 2 3 4 5 6 7 8 9 10
9 1 2 3 4 5 6 7 8 9 10
10 1 2 3 4 5 6 7 8 9 10
which makes me wonder...
Anyway, using FOR:
>> ideal-looper: func [
[ 'element [word!]
[ 'index [word!]
[ series [series!]
[ code [block!]
[ /local f
[ ] [
[ f: func reduce [element index] code
[ for i 1 length? series 1 [f series/:i i]
[ ]
>> ideal-looper char pos s: "hello" [
[ prin [pos char]
[ ideal-looper char pos s [prin " " prin char]
[ prin newline
[ ]
1 h h e l l o
2 e h e l l o
3 l h e l l o
4 l h e l l o
5 o h e l l o
I'd suggest reporting that to feedback.
HTH,
Gabriele.
--
Gabriele Santilli <[giesse--writeme--com]> - Amigan - REBOL programmer
Amiga Group Italia sez. L'Aquila -- http://www.amyresource.it/AGI/
