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From: wmb@MITCH.ENG.SUN.COM
Newsgroups: comp.lang.forth
Subject: Conditional compilation
Message-ID: <9102141437.AA13877@ucbvax.Berkeley.EDU>
Date: 14 Feb 91 04:05:40 GMT
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Reply-To: wmb%MITCH.ENG.SUN.COM@SCFVM.GSFC.NASA.GOV
Organization: The Internet
Lines: 28

> What about the simpler methods of
> conditional compiliation.  Have these all been rejected?  Why do we have
> to have the huge overhead of IFTRUE and such, rather than something
> simple and elegant, such as query-paren.

The trouble with query paren is that it doesn't nest, and it's a royal
pain to use if the stuff you are enclosing contains embedded right parens.

Another alternative is "conditional backslash".  It has problems too; it
doesn't nest, you need it at the start of every line, and it's
inconvenient to specify the equivalent of an "otherwise" clause with
this technique.

Are there some other commonly-used techniques I don't know about?

The overhead isn't huge; it can be implemented in about 150 bytes in
ANS Forth.  It's optional, too; it's in the extension portion of the
optional files wordset.  So, even if you implement the file wordset,
you don't have to have these words.  I can't think of any good reason
for a vendor not to supply them at least in source form though.

Interestingly, within hours of announcing their existence, I received
an enthusiastic personal email reply from a person who was very glad
to have them.

I guess its just a matter of personal taste.

Mitch Bradley, wmb@Eng.Sun.COM