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[REBOL] Re: variable variable

From: joel:neely:fedex at: 13-Jun-2001 0:34

Ammon Cooke wrote:
> Hold on while I, with my weak english skills, try to words > this so the gurus > know what I am talking about.... > > Ok, here we go... > > What I need is this: > > I am getting a value from a text-list: > > lst1-rnd: lst1/text: random/only lst1/data > > now create a variable: > > do reduce[to-set-word lst1-rnd: 1] > > now how do I access the value of the value of lst1-rnd > without explicitly calling it?? >
I'm still unclear what you mean by the phrase "without explicitly calling it". Let's make a simple example
>> pig
** Script Error: pig has no value ** Near: pig
>> cow
** Script Error: cow has no value ** Near: cow
>> duck
** Script Error: duck has no value ** Near: duck ; just to prove there's nothing up my sleeve... ;-) Now,
>> some-word: random/only [pig cow duck]
== duck
>> do reduce [to-set-word some-word "quack"]
== "quack" At this point, we've set the word DUCK (which formerly was not set to anything) to the string "quack". We can prove this by
>> duck
== "quack" To get at this word (and its current value) we must somehow remember what we called it. Its "name" is still in SOME-WORD, so we can do one of the following:
>> reduce reduce [some-word]
== ["quack"]
>> print reduce [some-word]
quack Once we change the value of SOME-WORD, we can't use it to get back to DUCK and hence to "quack". So, if you're going to change SOME-WORD, be sure to save its value somewhere, such as in a block. For example: repeat i 5 [ some-word: random/only [pig cow duck chicken horse dog cat] do reduce [to-set-word some-word i] if none? find barnyard some-word [append barnyard some-word] ] == [duck chicken cat dog] foreach indirect-word barnyard [ print [indirect-word do reduce [indirect-word]] ] duck 1 chicken 3 cat 4 dog 5 If you want to keep something, you have to remember where you put it, one way or another!
> PS the random function always picks the items from the list > in the SAME order. The reason I tried the random function > is to avoid that. What am i doing wrong?? >
Try using the /SEED refinement to RANDOM. -jn- ------------------------------------------------------------ Programming languages: compact, powerful, simple ... Pick any two! joel'dot'neely'at'fedex'dot'com