File Coverage

blib/lib/String/Substrings.pm

Criterion	Covered	Total	%
statement	28	28	100.0
branch	10	10	100.0
condition	5	6	83.3
subroutine	5	5	100.0
pod	0	1	0.0
total	48	50	96.0

package String::Substrings;

use 5.006;
use strict;
use warnings;

use Carp;

require Exporter;

our @ISA = qw(Exporter);

our %EXPORT_TAGS = ( 'all' => [ qw(
	substrings
) ] );

our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );

our @EXPORT = qw(
	substrings
);

our $VERSION = '0.02';

sub substrings($;$) {
    my ($string, $length) = @_;
    return undef unless defined $string;

    # paramter validation
    if (my $r = ref($string)) {
        croak "Please call me  `substrings STRING [,LENGTH]`
              but not with substrings $r, LENGTH";
    }
    if (defined($length) and (my $r = ref($length) or $length !~ /^\d+/)) {
        croak "Please call me `substrings STRING [,LENGTH]`
               but not with substrings '$string', $r";
    }


    my $strlength = length($string);
    my @s = ();
    if (defined $length) {
        return @s if $length == 0;
        push @s, map {substr $string, $_, $length} (0 .. $strlength-$length);
    } else {
        foreach my $length (1 .. $strlength) {
            push @s, map {substr $string, $_, $length}
                         (0 .. $strlength - $length);
        }
    }
    return @s;
}

1;
__END__