Hi.

In my code: 

#!/usr/bin/perl -w
use strict;

my $dna = 'atctcggataatgggataaaaatataggctataaatggcgccccggctaattttt';

if ($dna =~ /atg([acgt]+)(?!(taa|tag|tga))/xms)
{
    print $1;
}

[download]


I am trying to capture the very short string after the 'atg' and before (not including) either 'taa', 'tag', or 'tga'. I think I'm close but my regex is not working as expected.

Thank you monks and monkettes.

In reply to Simple regex question. Grouping with a negative lookahead assertion. by Anonymous Monk

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