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[REBOL] Re: Noob with a question

From: petr:krenzelok:seznam:cz at: 26-Mar-2009 6:08 napsal(a):
> Hi..... > > I'm a new-guy in the REBOLution ;) >
Hello and welcome! :-)
> At 62, I may be too old to make a good REBOLutionary, but I suppose > that advocacy is ageless. I'm a self-taught, amateur Perl and M(umps) > programmer. I've also had a long, hard look at Forth. I see in REBOL > what appears to be "some" Forth influence. Could I be correct? >
You are never too old to start with REBOL :-) As for Forth influence - yes, some ppl believe it has some influence in Forths (especially dialects), some do find some similarities in Lisp, even calling REBOL being a deparenthetised Lisp .... but - REBOL is special, not strictly functional language ...
> Anyway, so far I really enjoy REBOL - it's dead easy and very > intuitive. I'm using /Core on an OS X Intel box running the latest > Leopard patch. I don't believe /View will work on my machine. >
Hopefully some OS-X guys step in with the answer, but IIRC even View should work on OS-X?
> Question: > The manual states: > > The forall advances the variable position through the series, so when > it returns the variable is left at its tail: > > Therefore, the variable must be reset before it is used again: >
Not sure it has to: ->> forall colors [print first colors print index? colors] red 1 green 2 blue 3 ->> index? colors == 1 So, when out of the loop, the colors block is once again at its beginning. Even in a loop itself, it does not reach tail. I suggest following chapter describing how series positioning works. It is fundamental to understand it:
> However. when I try it out I get: > > >> > >> colors: [red green blue yellow orange] > == [red green blue yellow orange] > >> > >> forall colors [print first colors] > red > green > blue > yellow > orange > >> > >> print tail? colors > false >
As for me, I don't use forall much. I prefer foreach and for loops. Foreach when you don't need to know a position, just: foreach color colors [print color] And when I need to know the position, then I use old-school for loop :-) for color 1 length? colors 1 [print colors/:color]
> Thanks for the help and a great language! >
Once again - welcome here and enjoy! We have small community, but some ppl say very helpful :-) -pekr-