Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
SUPER(3)	      User Contributed Perl Documentation	      SUPER(3)

       SUPER - control superclass method dispatch

       Find the	parent method that would run if	this weren't here:

	   sub my_method
	       my $self	= shift;
	       my $super = $self->super('my_method'); #	Who's your daddy?

	       if ($want_to_deal_with_this)
		   # ...
		   $super->($self, @_)

       Or Ruby-style:

	   sub my_method
	       my $self	= shift;

	       if ($want_to_deal_with_this)
		   # ...

       Or call the super method	manually, with respect to inheritance, and
       passing different arguments:

	   sub my_method
	       my $self	= shift;

	       # parent	handles	args backwardly
	       $self->SUPER( reverse @_	);

       When subclassing	a class, you occasionally want to dispatch control to
       the superclass -- at least conditionally	and temporarily. The Perl
       syntax for calling your superclass is ugly and unwieldy:


       especially when compared	to its Ruby equivalent:


       It's even worse in that the normal Perl redispatch mechanism only
       dispatches to the parent	of the class containing	the method at compile
       time.  That doesn't work	very well for mixins and roles.

       This module provides nicer equivalents, along with the universal	method
       "super" to determine a class' own superclass. This allows you to	do
       things such as:

	   goto	&{$_[0]->super('my_method')};

       if you don't like wasting precious stack	frames.	(Because "super"
       returns a coderef, much like "can" in UNIVERSAL,	this doesn't break
       "use strict 'refs'".)

       If you are using	roles or mixins	or otherwise pulling in	methods	from
       other packages that need	to dispatch to their super methods, or if you
       want to pass different arguments	to the super method, use the "SUPER()"

	   $self->SUPER( qw( other arguments here ) );

       This module provides the	following functions and	methods:

	   This	function calls the super method	of the currently-executing
	   method, no matter where the super method is in the hierarchy.

	   This	takes no arguments; it passes the same arguments passed	to the
	   currently-executing method.

	   The module exports this function by default.

	   Note: you must have the appropriate "package" declaration in	place
	   for this to work.  That is, you must	have compiled the method in
	   which you use this function in the package from which you want to
	   use it.  Them's the breaks with Perl	5.

       "find_parent( $class, $method, $prune, $invocant	)"
	   Attempts to find a parent implementation of $method starting	with
	   $class.  If you pass	$prune,	it will	not ignore the method found in
	   that	package, if it exists there.  Pass $invocant if	the object
	   itself might	have a different idea of its parents.

	   The module does not export this function by default.	 Call it

       "get_all_parents( $invocant, $class )"
	   Returns all of the parents for the $invocant, if it supports	the
	   "__get_parents()" method or the contents of @ISA for	$class.	 You
	   probably oughtn't call this on your own.

	   Calls the super method of the currently-executing method.  You can
	   pass	arguments.  This is a method.

       Beware: if you do weird things with code	generation, be sure to name
       your anonymous subroutines.  See	Perl Hacks #57.

       Using "super" doesn't let you pass alternate arguments to your
       superclass's method. If you want	to pass	different arguments, use
       "SUPER" instead.	 D'oh.

       This module does	a small	amount of Deep Magic to	find the arguments of
       method calling "super()"	itself.	 This may confuse tools	such as

       In your own code, if you	do complicated things with proxy objects and
       the like, define	"__get_parents()" to return a list of all parents of
       the object to which you really want to dispatch.

       Created by Simon	Cozens,	"".  Copyright (c) 2003 Simon

       Maintained by chromatic,	<chromatic at wgz dot org> after version 1.01.
       Copyright (c) 2004-2009 chromatic.

       Thanks to Joshua	ben Jore for bug reports and suggestions.

       You may use and distribute this silly little module under the same
       terms as	Perl itself.

perl v5.32.1			  2022-03-26			      SUPER(3)


Want to link to this manual page? Use this URL:

home | help