Compiles once (since Perl notices the pattern doesn't change):

sub f { my $pat = $_[0]; (my $str = 'abba') =~ s/$pat//g; } 
f('b') 
f('b') 
f('b')

[download]

are you sure about that? basicly I do that, but the profiler claims that CORE:regcomp is called as often as f is executed...

I am using a rather ancient edition of perl (5.8.6), has this behavivour changed since then?

In reply to Re^2: precompiling regular expressions by Anonymous Monk
in thread precompiling regular expressions by Anonymous Monk

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