foo.pl

use v5.10;

my @a = (
    [ 'aaa', sub { say 'Apple' } ],
    [ 'bbb', sub { say 'Banana' } ],
    [ 'ccc', sub { say 'Carrot' } ],
);

my @r = map {
    '(' . $_->[0] . ')';
} @a;

my $r = '\G(?:' . join('|', @r) . ')';

my $i = 'aaabbbccc';

pos($i) = 3;

say "regex == /$r/";

$i =~ /$r/ or die "FAIL";

for (1..@a) {
    $a[$_ - 1]->[1]->() if defined ${$_};
}