Rechercher une page de manuel
Class::MakeMethods::Standard::Universal.3pm
Langue: en
Version: 2004-09-06 (fedora - 01/12/10)
Section: 3 (Bibliothèques de fonctions)
Sommaire
NAME
Class::MakeMethods::Standard::Universal - Generic MethodsSYNOPSIS
package MyObject; use Class::MakeMethods::Standard::Universal ( no_op => 'this', abstract => 'that', delegate => { name=>'play_music', target=>'instrument', method=>'play' }, );
DESCRIPTION
The Standard::Universal suclass of MakeMethods provides a [INCOMPLETE].Calling Conventions
When you "use" this package, the method names you provide as arguments cause subroutines to be generated and installed in your module.See ``Calling Conventions'' in Class::MakeMethods::Standard for more information.
Declaration Syntax
To declare methods, pass in pairs of a method-type name followed by one or more method names.Valid method-type names for this package are listed in ``METHOD GENERATOR TYPES''.
See ``Declaration Syntax'' in Class::MakeMethods::Standard and ``Parameter Syntax'' in Class::MakeMethods::Standard for more information.
METHOD GENERATOR TYPES
no_op - Placeholder
For each method name passed, returns a subroutine with the following characteristics:- *
- Does nothing.
You might want to create and use such methods to provide hooks for subclass activity.
Sample declaration and usage:
package MyObject; use Class::MakeMethods::Standard::Universal ( no_op => 'whatever', ); ... # Doesn't do anything MyObject->whatever();
abstract - Placeholder
For each method name passed, returns a subroutine with the following characteristics:- *
- Fails with an error message.
This is intended to support the use of abstract methods, that must be overidden in a useful subclass.
If each subclass is expected to provide an implementation of a given method, using this abstract method will replace the generic error message below with the clearer, more explicit error message that follows it:
Can't locate object method "foo" via package "My::Subclass" The "foo" method is abstract and can not be called on My::Subclass
However, note that the existence of this method will be detected by UNIVERSAL::can(), so it is not suitable for use in optional interfaces, for which you may wish to be able to detect whether the method is supported or not.
Sample declaration and usage:
package MyObject; use Class::MakeMethods::Standard::Universal ( abstract => 'whatever', ); ... package MySubclass; sub whatever { ... } # Failure MyObject->whatever(); # Success MySubclass->whatever();
call_methods - Call methods by name
For each method name passed, returns a subroutine with the following characteristics:- *
- Accepts a hash of key-value pairs, or a reference to hash of such pairs. For each pair, the key is interpreted as the name of a method to call, and the value is the argument to be passed to that method.
Sample declaration and usage:
package MyObject; use Class::MakeMethods::Standard::Universal ( call_methods => 'init', ); ... my $object = MyObject->new() $object->init( foo => 'Foozle', bar => 'Barbados' ); # Equivalent to: $object->foo('Foozle'); $object->bar('Barbados');
join_methods - Concatenate results of other methods
For each method name passed, returns a subroutine with the following characteristics:- *
- Has a list of other methods names as an arrayref in the 'methods' parameter. Required.
- *
- When called, calls each of the named method on itself, in order, and returns the concatenation of their results.
- *
- If a 'join' parameter is provided it is included between each method result.
- *
- If the 'skip_blanks' parameter is omitted, or is provided with a true value, removes all undefined or empty-string values from the results.
alias - Call another method
For each method name passed, returns a subroutine with the following characteristics:- *
- Calls another method on the same callee.
You might create such a method to extend or adapt your class' interface.
Sample declaration and usage:
package MyObject; use Class::MakeMethods::Standard::Universal ( alias => { name=>'click_here', target=>'complex_machinery' } ); sub complex_machinery { ... } ... $myobj->click_here(...); # calls $myobj->complex_machinery(...)
delegate - Use another object to provide method
For each method name passed, returns a subroutine with the following characteristics:- *
- Calls a method on self to retrieve another object, and then calls a method on that object and returns its value.
You might want to create and use such methods to faciliate composition of objects from smaller objects.
Sample declaration and usage:
package MyObject; use Class::MakeMethods::Standard::Universal ( 'Standard::Hash:object' => { name=>'instrument' }, delegate => { name=>'play_music', target=>'instrument', method=>'play' } ); ... my $object = MyObject->new(); $object->instrument( MyInstrument->new ); $object->play_music;
SEE ALSO
See Class::MakeMethods for general information about this distribution.See Class::MakeMethods::Standard for more about this family of subclasses.
Contenus ©2006-2024 Benjamin Poulain
Design ©2006-2024 Maxime Vantorre