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NAME

Method::Assert - Ensure instance and class methods are called properly

VERSION

version 0.0.1

SYNOPSIS

    package MyClass;

    use Method::Assert;
    use Carp qw(confess);

    sub new {
        my ($class, @args) = &class_method;
        my $self = {};
        bless $self, $class;
        $self->_init(@args);
        return $self;
    }

    sub _init {
        my ($self, @args) = @_; # Perl Critic prefers it this way
        &instance_method;       # still works
        ...
    }

    sub get_output_filename {
        &instance_method;
        return shift->{'output_filename'};
    }

    sub set_output_filename {
        my $self = &instance_method;
        confess("No parameter specified") unless @_;
        confess("File already exists") if -e $_[0];
        $self->{'output_filename'} = $_[0];
        return $self;
    }

DESCRIPTION

This module will export the two functions named below into the namespace of the package using it. These two functions are useful to do typical checks at the start of functions that are supposed to be either class or instance methods.

Always remember to call these functions as &class_method and &instance_method, or else they will not work properly!

If you call them as class_method() or instance_method() a new version of @_ will be initialized, and manipulation of @_ will not work properly.

FUNCTIONS

class_method

Use this function to check that the sub is called as a class method. If the sub is called as a function, or as an instance method this function will die.

If called in scalar context, will shift of the first argument of the @_ array and return that value. If called in list or void context it will not change @_.

instance_method

Use this function to check that the sub is called as an instance method. If the sub is called as a function, or as a class method this function will die.

If called in scalar context, will shift of the first argument of the @_ array and return that value. If called in list or void context it will not change @_.

CAVEATS

The two functions can NOT be called by the fully qualified method name because they are generated as closures in the calling package's namespace during import(). Writing use Method::Assert () will cause import() not to be executed, which doesn't not make sense. See the section on import in perldoc -f use for more information.

SEMANTIC VERSIONING

This module uses semantic versioning concepts from http://semver.org/.

SEE ALSO

SUPPORT

You can find documentation for this module with the perldoc command.

  perldoc Method::Assert

Websites

Bugs

Please report any bugs or feature requests to bug-method-assert at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Method-Assert. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

AUTHOR

  Robin Smidsrød <robin@smidsrod.no>

COPYRIGHT AND LICENSE

This software is copyright (c) 2010 by Robin Smidsrød.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.