File Coverage

blib/lib/String/CommonPrefix.pm

Criterion	Covered	Total	%
statement	19	21	90.4
branch	4	6	66.6
condition			n/a
subroutine	5	5	100.0
pod	1	1	100.0
total	29	33	87.8

package String::CommonPrefix;

our $DATE = '2014-12-10'; # DATE
our $VERSION = '0.01'; # VERSION

use 5.010001;
use strict;
use warnings;

use Exporter;
our @ISA = qw(Exporter);
our @EXPORT_OK = qw(
                       common_prefix
               );

sub common_prefix {
    return undef unless @_;
    my $i;
  L1:
    for ($i=0; $i < length($_[0]); $i++) {
        for (@_[1..$#_]) {
            if (length($_) < $i) {
                $i--; last L1;
            } else {
                last L1 if substr($_, $i, 1) ne substr($_[0], $i, 1);
            }
        }
    }
    substr($_[0], 0, $i);
}

1;
# ABSTRACT: Find prefix common to all strings

__END__