Yours is a very special case, because we know there's only one character after the last ".". Here is a benchmark I ran with my new patch: 
use Benchmark 'cmpthese';
my $str = join '.', 'a' .. 'z';
cmpthese(-5, {
  old => sub { (my $x = $str) =~ s/(.*)\..*/$1/ },
  new => sub { (my $x = $str) =~ s/.*\K\..*// },
});
__END__
new: 109650.19/s (n=578953)
old:  45258.35/s (n=241227)

[download]
... which is an incredible speed increase!

_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a job (NYC-area)
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: Re: New regex trick... by japhy
in thread New regex trick... by japhy

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