acme::damn(3pm) [debian man page]

Damn(3pm)						User Contributed Perl Documentation						 Damn(3pm)

NAME

       Acme::Damn - 'Unbless' Perl objects.

SYNOPSIS

	 use Acme::Damn;

	 my $ref = ... some reference ...
	 my $obj = bless $ref , 'Some::Class';

	 ... do something with your object ...

	    $ref = damn $obj;	# recover the original reference (unblessed)

	 ... neither $ref nor $obj are Some::Class objects ...

DESCRIPTION

       Acme::Damn provides a single routine, damn(), which takes a blessed reference (a Perl object), and unblesses it, to return the original
       reference.

   EXPORT
       By default, Acme::Damn exports the method damn() into the current namespace. Aliases for damn() (see below) may be imported upon request.

   Methods
       damn object
	   damn() accepts a single blessed reference as its argument, and returns that reference unblessed. If object is not a blessed reference,
	   then damn() will "die" with an error.

       bless reference
       bless reference [ , package ]
       bless reference [ , undef ]
	   Optionally, Acme::Damn will modify the behaviour of "bless" to allow the passing of an explicit "undef" as the target package to invoke
	   damn():

	       use Acme::Damn  qw( bless );

	       my  $obj = ... some blessed reference ...;

	       # the following statements are equivalent
	       my  $ref = bless $obj , undef;
	       my  $ref = damn $obj;

	   NOTE: The modification of "bless" is lexically scoped to the current package, and is not global.

   Method Aliases
       Not everyone likes to damn the same way or in the same language, so Acme::Damn offers the ability to specify any alias on import, provided
       that alias is a valid Perl subroutine name (i.e. all characters match "w").

	 use Acme::Damn qw( unbless );
	 use Acme::Damn qw( foo );
	 use Acme::Damn qw( unblessthyself );
	 use Acme::Damn qw( recant );

       Version 0.02 supported a defined list of aliases, and this has been replaced in v0.03 by the ability to import any alias for "damn()".

WARNING

       Just as "bless" doesn't call an object's initialisation code, "damn" doesn't invoke an object's "DESTROY" method. For objects that need to
       be "DESTROY"ed, either don't "damn" them, or call "DESTROY" before judgement is passed.

ACKNOWLEDGEMENTS

       Thanks to Claes Jacobsson <claes@surfar.nu> for suggesting the use of aliases, and Bo Lindbergh <blgl@cpan.org> for the suggested
       modification of "bless".

SEE ALSO

       bless, perlboot, perltoot, perltooc, perlbot, perlobj.

AUTHOR

       Ian Brayshaw, <ian@onemore.org>

COPYRIGHT AND LICENSE

       Copyright 2003-2012 Ian Brayshaw

       This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.14.2							    2012-02-14								 Damn(3pm)

UNIVERSAL(3pm)						 Perl Programmers Reference Guide					    UNIVERSAL(3pm)

NAME

       UNIVERSAL - base class for ALL classes (blessed references)

SYNOPSIS

	   $is_io = $fd->isa("IO::Handle");
	   $is_io = Class->isa("IO::Handle");

	   $sub = $obj->can("print");
	   $sub = Class->can("print");

	   use UNIVERSAL qw( isa can VERSION );
	   $yes = isa $ref, "HASH" ;
	   $sub = can $ref, "fandango" ;
	   $ver = VERSION $obj ;

DESCRIPTION

       "UNIVERSAL" is the base class which all bless references will inherit from, see perlobj.

       "UNIVERSAL" provides the following methods and functions:

       $obj->isa( TYPE ), CLASS->isa( TYPE ), isa( VAL, TYPE )
	       C<TYPE> is a package name
	       $obj is a blessed reference or a string containing a package name
	       C<CLASS> is a package name
	       C<VAL> is any of the above or an unblessed reference

	   When used as an instance or class method ("$obj-"isa( TYPE )>), "isa" returns true if $obj is blessed into package "TYPE" or inherits
	   from package "TYPE".

	   When used as a class method ("CLASS-"isa( TYPE )>; sometimes referred to as a static method), "isa" returns true if "CLASS" inherits
	   from (or is itself) the name of the package "TYPE" or inherits from package "TYPE".

	   When used as a function, like

	      use UNIVERSAL qw( isa ) ;
	      $yes = isa $h, "HASH";
	      $yes = isa "Foo", "Bar";

	   or

	      require UNIVERSAL ;
	      $yes = UNIVERSAL::isa $a, "ARRAY";

	   , "isa" returns true in the same cases as above and also if "VAL" is an unblessed reference to a perl variable of type "TYPE", such as
	   "HASH", "ARRAY", or "Regexp".

       $obj->can( METHOD ), CLASS->can( METHOD ), can( VAL, METHOD )
	   "can" checks if the object or class has a method called "METHOD". If it does then a reference to the sub is returned. If it does not
	   then undef is returned.  This includes methods inherited or imported by $obj, "CLASS", or "VAL".

	   "can" cannot know whether an object will be able to provide a method through AUTOLOAD, so a return value of undef does not necessarily
	   mean the object will not be able to handle the method call. To get around this some module authors use a forward declaration (see perl-
	   sub) for methods they will handle via AUTOLOAD. For such 'dummy' subs, "can" will still return a code reference, which, when called,
	   will fall through to the AUTOLOAD. If no suitable AUTOLOAD is provided, calling the coderef will cause an error.

	   "can" can be called as a class (static) method, an object method, or a function.

	   When used as a function, if "VAL" is a blessed reference or package name which has a method called "METHOD", "can" returns a reference
	   to the subroutine.  If "VAL" is not a blessed reference, or if it does not have a method "METHOD", undef is returned.

       VERSION ( [ REQUIRE ] )
	   "VERSION" will return the value of the variable $VERSION in the package the object is blessed into. If "REQUIRE" is given then it will
	   do a comparison and die if the package version is not greater than or equal to "REQUIRE".

	   "VERSION" can be called as either a class (static) method, an object method or or a function.

       These subroutines should not be imported via "use UNIVERSAL qw(...)".  If you want simple local access to them you can do

	 *isa = &UNIVERSAL::isa;

       to import isa into your package.

perl v5.8.0							    2002-06-01							    UNIVERSAL(3pm)