File Coverage

lib/Unknown/Values.pm

Criterion	Covered	Total	%
statement	40	41	97.5
branch	7	8	87.5
condition	5	6	83.3
subroutine	12	12	100.0
pod	1	1	100.0
total	65	68	95.5

use strict;
use warnings;

# ABSTRACT: Use 'unknown' values instead of undef ones

package Unknown::Values;
$Unknown::Values::VERSION = '0.101';
use 5.01000;
use Unknown::Values::Instance;
use Unknown::Values::Instance::Fatal;
use Unknown::Values::Instance::Object;
use Carp ();

use Scalar::Util 'blessed';

sub import {
    my $class         = shift;
    my $caller        = caller;
    my $unknown_class = 'Unknown::Values::Instance';
    if (@_) {
        if ( ':FATAL' eq $_[0] ) {
            $unknown_class = 'Unknown::Values::Instance::Fatal';
        }
        elsif ( ':OBJECT' eq $_[0] ) {
            $unknown_class = 'Unknown::Values::Instance::Object';
        }
        else {
            Carp::croak("I don't know how to create an Unknown::Values object of type '$_[0]'");
        }
    }
    my $unknown        = $unknown_class->new;
    my $unknown_sub    = "${caller}::unknown";
    my $is_unknown_sub = "${caller}::is_unknown";
    no strict 'refs';
    *$unknown_sub    = sub {$unknown};
    *$is_unknown_sub = \&is_unknown;
}

sub is_unknown(_) {
    defined $_[0]
      && blessed( $_[0] )
      && (
        # Unknown::Values::Instance::Object overrides isa()
        ( 'Unknown::Values::Instance::Object' eq ref $_[0] ) || $_[0]->isa("Unknown::Values::Instance")
      );
}

1;

__END__