Hi, Monks,

I have a file with 861_600 lines of text. I wish to find the earliest line that exactly matches any of a small set of strings. Here's part of my current code:

use List::Util 'first';
use File::Map 'map_handle';
open my $fh, '<', 'huge_file';
map_handle my $map, $fh;
my $string = first {$_ ~~ @strings} ($map =~ m"^(.*)$"gm);

[download]

Does this stop searching on the first match? If not, would the following stop searching on the first match?

use List::MoreUtils 'firstval';
use File::Map 'map_handle';
open my $fh, '<', 'huge_file';
map_handle my $map, $fh;
my $string = firstval {$_ ~~ @strings} ($map =~ m"^(.*)$"gm);

[download]

If not, would anything stop searching on the first match? Any other advice for how to speed up this code would be much appreciated.

$_="msh210";$"=$\;@_=@{[split//,uc]}[2,0];$_="@_$\1";$\=$/;++$_[0]for$...1;print lc substr crypt($_,"@_"),1,6

In reply to grepping a large file and stopping on first match to a list by msh210

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