warnings::method - Produces warnings if methods are called as functions

This document describes warnings::method version 0.10

    use warnings::method;         # installs the check routine lexically
    use warnings::method -global; # or installs it globally
	use warnings 'syntax';        # enables the check routine

    package Foo;
    sub bar :method{
	# ...
    }

    Foo->bar(); # OK

    # the following cases warnings "Method Foo::bar() called as a function"

    Foo::bar();                  # WARN

    my $method_ref = \&Foo::bar; # WARN

    sub f{
        goto &Foo::bar;          # WARN
    }

You shouldn't call a method as a function, e.g. UNIVERSAL::isa($o, 'ARRAY'). It's considered harmful, because such code doesn't call overridden methods in any classes. This pragmatic module produces warnings if methods are called as functions. Here, methods are subroutines declared with the :method attribute.

This module scans the compiled syntax tree, checks function calls and produces warnings when dangerous function calls are detected. All the processes finish in compile time, so this module has no effect on run-time behavior.

The UNIVERSAL::isa and UNIVERSAL::can distributions are modules based on the same concept, but they produce warnings at run time.

Installs the method check routine with lexical scope.

Note that the lexicality is limited before 5.10.0.

Installs the method check routine with global scope, where this pragma checks all programs.

Enables/Disables the method check routine.

Note that the syntax warning is defined by default, so you can always use it even if warnings::method is not loaded.

Perl 5.8.1 or later, and a C compiler.

No bugs have been reported.

Please report any bugs or feature requests to bug-warnings-method@rt.cpan.org/, or through the web interface at http://rt.cpan.org/.

UNIVERSAL.

UNIVERSAL::isa.

UNIVERSAL::can.

perllexwarn.

warnings::unused.

Goro Fuji <gfuji(at)cpan.org>

Copyright (c) 2008, Goro Fuji <gfuji(at)cpan.org>. Some rights reserved.

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