Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!ucsd!ucbvax!ARIZONA.EDU!ralph
From: ralph@ARIZONA.EDU ("Ralph Griswold")
Newsgroups: comp.lang.icon
Subject: Re:  cset comparisons
Message-ID: <8909121438.AA07886@megaron.arizona.edu>
Date: 12 Sep 89 14:38:14 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Distribution: inet
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The correct comparison operation to use is

	c1 === c2

provided both c1 and c2 are csets (=== does no type conversion).  For
csets, the bits are compared in about as fast a way as possible.

If you write

	c1 == c2

both operands are converted to strings and then compared.  Slow and
it also requires storage allocation.

Incidentally, to find out if a cset is empty, it's probably better to use

	*c1 = 0

I'm not positive about this; would have to do timings.  The size of
a cset is computed only when it's first needed.  IF it's used the second
time, it's available without additional computation.

  Ralph Griswold / Dept of Computer Science / Univ of Arizona / Tucson, AZ 85721
  +1 602 621 6609   ralph@Arizona.EDU  uunet!arizona!ralph