Acme-Lexical-Thief

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README  view on Meta::CPAN

       if (steal $foo) { ... }   # not this!
   
       # this works...
       if (do { steal $foo; defined $foo })
       {
          # ... but $foo won't exist in this block!
          ...
       }

    If you attempt to steal a variable which does not exist, then a run-time
    exception will be thrown.

WHY YOU SHOULD NOT USE THIS MODULE
    When people declare lexical (`my`) variables within a sub, they (quite
    reasonably) expect these to stay local to the sub. If they rename those
    variables, change them (say replacing a hashref with a hash), drop them or
    whatever, then they don't expect code outside the sub to pay much
    attention.

    Peeking at your caller's lexicals breaks those expectations.

lib/Acme/Lexical/Thief.pm  view on Meta::CPAN

   if (steal $foo) { ... }   # not this!
   
   # this works...
   if (do { steal $foo; defined $foo })
   {
      # ... but $foo won't exist in this block!
      ...
   }

If you attempt to steal a variable which does not exist, then a run-time
exception will be thrown.

=head1 WHY YOU SHOULD NOT USE THIS MODULE

When people declare lexical (C<my>) variables within a sub, they (quite
reasonably) expect these to stay local to the sub. If they rename those
variables, change them (say replacing a hashref with a hash), drop them
or whatever, then they don't expect code outside the sub to pay much
attention.

Peeking at your caller's lexicals breaks those expectations.

t/02thievery.t  view on Meta::CPAN

=head1 PURPOSE

Tests that variable stealing works.

Scalars, arrays and hashes are tested; multiple call stack levels are tested;
decimal and hexadecimal notations for call stack levels are tested; the syntax
with and without parentheses is tested; line breaks and other insignicant
white space in the syntax is tested.

There is a test that an exception is thrown when you try to steal a
non-existant variable.

There is a test that stolen variables are writable.

=head1 AUTHOR

Toby Inkster E<lt>tobyink@cpan.orgE<gt>.

=head1 COPYRIGHT AND LICENCE

t/02thievery.t  view on Meta::CPAN

		'@A'  => [qw/ A-quux /],
		'@B'  => [qw/ B-bar /],
		'%C'  => { C => 'bar' },
	},
	'steal can steal scalars, arrays and hashes from several call stack depths',
);

like(
	exception { foo() },
	qr{steal..x. failed. caller has no .x defined},
	'throws an exception when unable to steal',
);

sub xxx1 {
	steal $x;
	$x++;
}

sub xxx2 {
	my $x = 41;
	xxx1(123);