The general case would be to use a Schwartzian Transform but in this simplistic case for small values of n you can just perform the extractions within the sort:

use strict;
use warnings;

use Test::More tests => 1;

my @in   = qw/a-3 a-1 a-2/;
my @want = qw/a-1 a-2 a-3/;

my @have = sort { ($a =~ /(\d+)/)[0] <=> ($b =~ /(\d+)/)[0] } @in;
is_deeply \@have, \@want;

[download]

See also the FAQ: How do I sort an array by (anything)?

PS. Here's the same thing but with substr:

use strict;
use warnings;

use Test::More tests => 1;

my @in   = qw/a-3 a-1 a-2/;
my @want = qw/a-1 a-2 a-3/;

my @have = sort { substr ($a, 2) <=> substr ($b, 2) } @in;
is_deeply \@have, \@want;

[download]

🦛

In reply to Re: How can I do a numeric sort on a substring? by hippo
in thread How can I do a numeric sort on a substring? by misterperl

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