#/usr/bin/perl -w

use strict;
use Benchmark;

sub f {
  our %d;
  local *d = shift;
  $d{$_}=$_ foreach (0 .. 200);

}

sub b {
  my $d = shift;
  $$d{$_}=$_ foreach (0 .. 200);
}

my %c;

timethese (100000, {
   'f' => '&f(\%c)',
   'b' => '&b(\%c)',
});

##</code><code>##

Benchmark: timing 100000 iterations of b, f...
         b: 83 wallclock secs (67.82 usr + 14.38 sys = 82.20 CPU) @ 1216.55/s (n=100000)
         f: 80 wallclock secs (65.86 usr + 13.95 sys = 79.81 CPU) @ 1252.98/s (n=100000)