I wonder ... if all you were doing was some transliteration why would you bother with the lines at all? Read and process say 64 KB at once. As I said, not sure this is doable in your case.

Second ... why would you spend time "figuring out reasonable character classes? If you have the mapping hash, just build the tr/// out of it. I just tried to benchmark the difference between tr/a-z/A-Z/ and tr/abcdef...xyz/ABCDEF...ZYX/ and the later actually came out a tiny little bit faster. So you could either have the tr/// generated from the hash and copy the result into the script or use string eval to define a subroutine to do the transliteration.  my $sub = eval 'sub { my $x = shift(); $x=~ tr/' . join('', keys %h) . '/' . join('', values %h) . '/; return $x}'; or something. If the loop is simple enough you could eval the whole loop so that you do not waste time by the subroutine call for each line. Or am I missing something?

Jenda
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In reply to Re^3: The indisputable speed of tr/// by Jenda
in thread The indisputable speed of tr/// by radiantmatrix

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