use strict; use warnings; use Benchmark qw(cmpthese); print "perl version $] \n"; my $rx = qr{X}xms; cmpthese(-1, { 'qr_bound' => sub { 'Y' =~ $rx ; }, 'qr_interp' => sub { 'Y' =~ / $rx / ; }, 'qr_interp_o' => sub { 'Y' =~ / $rx /o; }, 'm_empty' => sub { 'Y' =~ //; }, 'm_empty_o' => sub { 'Y' =~ //o; }, });