And here's the benchmark to prove it:
#!/usr/bin/perl -w
use strict;
use Benchmark;
Benchmark::cmpthese(10_000, {
'C-style' => sub { for (my $i = 0; $i <= 1000; $i++){ undef } },
'foreach' => sub { for my $i (0..1000) { undef } }
});
__END__
Benchmark: timing 10000 iterations of C-style, foreach...
C-style: 5 wallclock secs ( 5.20 usr + 0.00 sys = 5.20 CPU) @ 19
+23.08/s (n=10000)
foreach: 4 wallclock secs ( 3.73 usr + 0.00 sys = 3.73 CPU) @ 26
+80.97/s (n=10000)
Rate C-style foreach
C-style 1923/s -- -28%
foreach 2681/s 39% --
By the way: does perl have absolutely _no_ optimisation for for (;;) without any expressions in its parens? I find that a bit hard to believe.
2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$
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