#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

my $bob = 'bob';

sub match {
    my ($string, $regex) = @_;
    say $string, "\t", $regex;
    my @chars = split //, $regex;
    for my $pos (1 .. $#chars) {
        my $re_part = join q(), @chars[0 .. $pos];
        return 1 if eval { $string =~ /^($re_part)$/ and length $1 };
    }
    return 0
}

for my $regex ( 'bobly',
                'bo*[a-z].',
                'bob',
                'bo(x)?bcd',
                'fred',
                'o*',
              ) {
    say match('bob', $regex);
}