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Internals(3pm)


NAME

   Internals - Write-protect variables, manipulate refcounts

SYNOPSIS

     use Internals qw(IsWriteProtected SetReadOnly SetReadWrite GetRefCount SetRefCount);

     use Internals qw(:all);

     $object = My::Class->new(@parameters);

     SetReadOnly($object);

     SetReadWrite($object);

     if (IsWriteProtected($object)) { ... }

     $value = GetRefCount($object);

     SetRefCount($object,$value);

   or

     package My::Class;

     use Internals;

     @ISA = qw(Internals);

     $object = My::Class->new(@parameters)->SetReadOnly();

     $object->SetReadWrite();

     if ($object->IsWriteProtected()) { ... }

     $value = $object->GetRefCount();

     $object->SetRefCount($value);

   or

     use Internals qw(IsWriteProtected SetReadOnly SetReadWrite GetRefCount SetRefCount);

     use Internals qw(:all);

     SetReadOnly(\$scalar);

     SetReadOnly(\@array);

     SetReadOnly(\%hash);

     SetReadOnly(\$hash{$element});

     SetReadOnly(\$reference);

   etc.

DESCRIPTION

   This module allows you to write-protect and write-enable your Perl
   variables, objects and data structures.

   Moreover, the reference count of any Perl variable can be read and set.

   You can never pass the object directly on which to perform the desired
   action, you always have to pass a reference to the variable or data
   structure in question.

   This comes in handy for objects and anonymous data structures, where
   you only have a reference anyway!

   BEWARE: This module is DANGEROUS!

   DO NOT attempt to unlock Perl's built-in variables!

   DO NOT manipulate reference counts unless you know exactly what you're
   doing!

   ANYTHING might happen! Hell might break loose! ":-)"

   YOU HAVE BEEN WARNED!

VERSION

   This man page documents "Internals" version 1.1.

AUTHOR

     Steffen Beyer
     mailto:sb@engelschall.com
     http://www.engelschall.com/u/sb/download/

COPYRIGHT

   Copyright (c) 2001 by Steffen Beyer. All rights reserved.

LICENSE

   This package is free software; you can redistribute it and/or modify it
   under the same terms as Perl itself, i.e., under the terms of the
   "Artistic License" or the "GNU General Public License".

   Please refer to the files "Artistic.txt" and "GNU_GPL.txt" in this
   distribution for details!

DISCLAIMER

   This package is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

   See the "GNU General Public License" for more details.



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