NAME

Class::NonOO - Use methods as functions with an implicit singleton

SYNOPSYS

In a module:

package MyModule;

use Class::NonOO;

...

sub my_method {
   my ($self, @args) = @_;
   ...
}

as_function
  export => [ 'my_method' ], # methods to export
  args   => [ ];             # constructor args

The module can be be used with a function calling style:

use MyModule;

...

my_method(@args);

DESCRIPTION

This module allows you to turn a class into a module that exports methods as functions that use an implicit singleton. This allows you to provide a "hybrid" object-oriented/functional interface.

EXPORTS

as_function

as_function
  export      => [ ... ], # @EXPORT
  export_ok   => [ ... ], # @EXPORT_OK (optional)
  export_tags => { ... }, # %EXPORT_TAGS (optional)
  args        => [ ... ], # constructor args (optional)
  global      => 0;       # no global state (default)

This wraps methods in a function that checks the first argument. If the argument is an instance of the class, then it assumes it is a normal method call. Otherwise it assumes it is a function call, and it calls the method with the singleton instance.

If the export option is omitted, it will default to the contents of the @EXPORT variable. The same holds for the export_ok and export_tags options and the @EXPORT_OK and %EXPORT_TAGS variables, respectively.

Note that this will not work properly on methods that take an instance of the class as the first argument.

By default, there is no global state. That means that there is a different implicit singleton for each namespace. This offers some protection when the state is changed in one module, so that it does not affect the state in another module.

If you want to enable global state, you can set global to a true value. This is not recommended for CPAN modules.

You might work around this by using something like

local %MyClass::_DEFAULT_SINGLETONS;

but this is not recommended. If you need to modify state and share it across modules, you should be passing around individual objects instead of singletons.

SEE ALSO

Class::Exporter is a similar module.

AUTHOR

Robert Rothenberg, <rrwo at cpan.org>

LICENSE AND COPYRIGHT

Copyright 2015-2016 Robert Rothenberg.

This program is free software; you can redistribute it and/or modify it under the terms of the the Artistic License (2.0). You may obtain a copy of the full license at:

http://www.perlfoundation.org/artistic_license_2_0

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