Path: utzoo!utgpu!watmath!att!dptg!rutgers!mailrus!ncar!ico!ism780c!haddock!karl
From: karl@haddock.ima.isc.com (Karl Heuer)
Newsgroups: comp.lang.c
Subject: Re: What I'd really like to see in an if-statement...
Message-ID: <14224@haddock.ima.isc.com>
Date: 8 Aug 89 01:47:19 GMT
References: <5024@alvin.mcnc.org> <1300@atanasoff.cs.iastate.edu> <456@helios.prosys.se> <14521@bfmny0.UUCP>
Reply-To: karl@haddock.ima.isc.com (Karl Heuer)
Organization: Interactive Systems, Boston
Lines: 16

Btw, one of my own pet ideas for "D" is the same notation in a loop construct:
	for (lo <= var < hi) ...
which would mean the same thing as C's
	for (var = lo; var < hi; ++var) ...
except that hi would be evaluated only once, and it would be illegal to change
the value of var within the loop.  (I.e., it would be your standard for-loop
as in BASIC/FORTRAN/PASCAL.)  All eight sensible combinations of relational
operators would be allowed.  (The construct
	for (hi > var >= lo) ...
would step through the same values via a decrementing loop.)

The only other proposal I've seen for such a feature uses notation like
	for (var in [lo, hi)) ...
but the syntax for the half-open interval is ugly.  (And "[lo, hi[" is worse.)

Karl W. Z. Heuer (ima!haddock!karl or karl@haddock.isc.com), The Walking Lint