Re: Speed of increment operators



axel@xxxxxxxxxxxxxxxxxxxxxx wrote:
Dr.Ruud <rvtol+news@xxxxxxxxxxxx> wrote:
The first two lines of my smaller Perl scripts often look like:

#!/usr/bin/perl
use strict; use warnings; ++$|;

On a slightly different track, is there any different in execution
speed between ++$i and $i++ in Perl. I seem to remember that there
was such a difference in C++ but may be mistaken.

perl -MO=Deparse -e'$x = 5; $x++; ++$x;'
$x = 5;
++$x;
++$x;
-e syntax OK

Seeing as how Perl optimizes away the post-fix notation when called in
a void context, I'm going to go on a limb and say "no, it doesn't make
a difference". In any case in which Perl would not optimize it away,
then you're doing something differently when you call one instead of
the other, and so speed should not be your concern.

Paul Lalli

.



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