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in reply to Re: /o is dead, long live qr//!
in thread /o is dead, long live qr//!

Actually, I tend to shy away from using qr, because they are dead slow when interpolating into larger constructs. Building large regexes from smaller parts is something I do often. Here's a benchmark showing a dramatic difference:
#!/usr/bin/perl use strict; use warnings; use Benchmark qw /cmpthese/; cmpthese -2 => { qq => 'my $x = qq "[a]"; $x = qq "[a]$x" for 1 .. 100; "" =~ /$x +/', qr => 'my $x = qr "[a]"; $x = qr "[a]$x" for 1 .. 100; "" =~ /$x +/', } __END__ Benchmark: running qq, qr for at least 2 CPU seconds... qq: 6 wallclock secs ( 2.11 usr + 0.03 sys = 2.14 CPU) @ 5902.80/ +s (n=12632) qr: 4 wallclock secs ( 2.03 usr + 0.00 sys = 2.03 CPU) @ 39.90/s +(n=81) Rate qr qq qr 39.9/s -- -99% qq 5903/s 14693% --

Abigail