comment on

lc is much faster, it seems to me, though both are very fast (each of these tests below is for 1m comparisons, so regexp had 150K/s, and lc 1830K/s).

Benchmark: timing 10 iterations of RegExp, lc...
    RegExp: 66 wallclock secs (66.20 CPU) @  0.15/s (n=10)
        lc:  6 wallclock secs ( 5.47 CPU) @  1.83/s (n=10)
[download]

#!/usr/bin/perl

use warnings;
use strict;

use Benchmark;

use constant SIZE => 1000;

our @a1 = map { "a".$_ } (1..SIZE);
our @a2 = map { "A".$_ } (1..SIZE);

sub use_re
{
    my $count = 0;
    foreach my $i (@a1) {
        foreach my $j (@a2) {
            if ($i =~ /^\Q$j\E$/i) {
                $count++;
            }
        }
    }
    die unless $count == SIZE;
}

sub use_lc
{
    my $count = 0;
    foreach my $i (@a1) {
        foreach my $j (@a2) {
            if (lc $i eq lc $j) {
                $count++;
            }
        }
    }
    die unless $count == SIZE;
}

timethese(10, {
    RegExp => \&use_re,
    lc => \&use_lc,
});
[download]

--
sgifford's Web page

In reply to Re: Comparing strings case insensitive by sgifford
in thread Comparing strings case insensitive by zemane

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