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[REBOL] Re: can't quite get it right...

From: joel:neely:fedex at: 8-Sep-2001 5:26

Allen Kamp wrote:
> > Unfortunately, there are situations in which a LOGIC! value > > is expected -- which ALL may not supply -- so one may have > > to resort to saying > > > > to-logic all [#"A" <= ch ch <= #"Z"] > > In this case I would prefer to use > found? all [#"A" <= ch ch <= #"Z"] > > as (IMHO) "found?" signals the intention of the function > better than "to-logic" >
YMMV. TMTOWTDI. When using ALL as a "short-circuit" version of AND, my intent is to produce a boolean value. In my mental model for that case, I'm not asking whether a result was found, but asking for the boolean equivalent of the result. This is necessary because of the pun REBOL makes with NONE (just as LISP did with nil). If I were using ALL in a chain-of-defaults context... all [find this-frame "sometag" find prior-frame "sometag" find base-frame "sometag" find base-frame "default"] I'd more likely be thinking in terms of whether a result were FOUND? or not. As long as we're talking about FOUND?, that brings up the possibility of solving the original problem with FIND, as in
>> find charset [#"A" - #"Z"] #"S"
== true
>> find charset [#"A" - #"Z"] #"$"
== none
or (of course) the above prefixed with FOUND? if a boolean result is required. -jn- -- ------------------------------------------------------------ Programming languages: compact, powerful, simple ... Pick any two! joel'dot'neely'at'fedex'dot'com