Would it give a speed improvement to prepare the regex in advance with qr//?

my $re = qr/^CPXX1|^KLXX1|^KMXX1|^MEXX1|^PAXX1|^PMXX1|^SLXX1|^SZXX1|^WXXX1|^YZXX1/;
...
print OFILE unless /$re/;
...

I think other monks have already suggested using a buffer to reduce the number of write, this would probably give a fairly major improvement.

In reply to Re: perl performance vs egrep by YetAnotherDave
in thread perl performance vs egrep by dba

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