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From: pjack...@online.no (Peter J. Acklam)
Newsgroups: comp.lang.perl.misc
Subject: When does (pre|post)increment happen?
Date: 13 Jan 2003 00:51:28 -0800
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The following results confuse me.  I expected
to get 0.5 and 1:

   $ perl -wle '$n = 1 ; print $n / ++$n'
   1

   $ perl -wle '$n = 1 ; print $n / $n++'
   2

In the first case, I expected to get 0.5 because
the preincrement would increment $n so the numerator
became 2, thus giving 1/2 = 0.5.

In the second case, I expected to get 1 because
the postincrement would increment $n *after* the
division was performed, thus giving 1/1 = 1.

I'd be thankful if anyone would explain...

Peter