There's a few ways of doing this. Here's one: 

$ perl -Mstrict -Mwarnings -E '
my $x = q{ac-t-c-t-g};
$x =~ /[acgt]/g for (1..4);
say substr($x, 0, pos($x));
'
ac-t-c
$ perl -Mstrict -Mwarnings -E '
my $x = q{a----c-tg-ggg};
$x =~ /[acgt]/g for (1..4);
say substr($x, 0, pos($x));
'
a----c-tg

[download]

-- Ken

In reply to Re: Perl match by kcott
in thread Perl match by nicholaspr

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