There are still plenty more ways to skin that cat :)
Why subtract and add; when you can just subtract. And why compare to zero when it is unnecessary:
#! perl
use strict;
use warnings;
use Benchmark qw( cmpthese );
my $n = 1e6;
my $foreach_loop_total = 0;
my $c_for_loop_total = 0;
my $while_loop_total = 0;
my $while_loop_total2 = 0;
cmpthese 100, {
foreach_loop => \&foreach_loop,
c_for_loop => \&c_for_loop,
while_loop => \&while_loop,
while_loop2 => \&while_loop2,
};
print "\$foreach_loop_total = $foreach_loop_total\n";
print "\$c_for_loop_total = $c_for_loop_total\n";
print "\$while_loop_total = $while_loop_total\n";
print "\$while_loop_total2 = $while_loop_total2\n";
sub foreach_loop {
$foreach_loop_total -= $_ for -$n .. 0;
}
sub c_for_loop {
for (my $j = $n; $j >= 0; --$j) {
$c_for_loop_total += $j;
}
}
sub while_loop {
my $n = $n;
$while_loop_total += $n-- while $n;
}
sub while_loop2 {
use integer;
my $n = $n;
$while_loop_total2 += $n-- while $n;
}
__END__
C:\test>junk
Rate c_for_loop while_loop while_loop2 foreach_loo
+p
c_for_loop 4.94/s -- -22% -39% -44
+%
while_loop 6.31/s 28% -- -22% -28
+%
while_loop2 8.07/s 63% 28% -- -8
+%
foreach_loop 8.76/s 77% 39% 8% -
+-
$foreach_loop_total = 50000050000000
$c_for_loop_total = 50000050000000
$while_loop_total = 50000050000000
$while_loop_total2 = 50000050000000
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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