view release on metacpan or  search on metacpan

lib/Devel/WatchVars.pm  view on Meta::CPAN

=encoding utf8

=cut

use utf8;
use strict;
use warnings;
no overloading;

use Carp;
use Scalar::Util qw(weaken readonly reftype);

use namespace::clean;

###########################################################

our $VERSION = "v1.0.5";

use Exporter qw(import);
our @EXPORT = qw(watch unwatch);

lib/Devel/WatchVars.pm  view on Meta::CPAN

    $reftype =~ /^(?:SCALAR|REF)\z/ || 
        croak "You didn't pass a SCALAR (by reference), you passed a ",
              $reftype       ? "$reftype (by reference)"
            : defined($sref) ? "non-reference"
            :                  "undef";

    !readonly($$sref)           || croak "Can't watch a readonly scalar";

    my $value = $$sref;
    my $self  = tie $$sref, $TIE_PACKAGE, $name, $value;
    weaken($$self{sref} = $sref);
}

###########################################################

sub unwatch(\$) {
    my($tref) = @_;
    ref($tref) eq "SCALAR"      || croak "You didn't pass a scalar (by reference)";
    my $self = tied $$tref      || croak "Can't unwatch something that isn't tied";
    $self->isa($TIE_PACKAGE)    || croak "Can't unwatch something that isn't watched";
    my($sref, $value) = @$self{sref => "value"};