Man pages sections > man3 > Class::MakeMethods::Standard::Universal

Class::MakeMethods::Standard::Universal - Generic Methods

MakeMethods::Standard::Universal(3pm) User Contributed Perl Documentation MakeMethods::Standard::Universal(3pm)

NAME

Class::MakeMethods::Standard::Universal - Generic Methods

SYNOPSIS

  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 overridden 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 facilitate 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.
2016-06-10 perl v5.22.2