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Perl::Critic::Policy::BuiltinFunctions::ProhibitUniversalCan(3pm) User Contributed Perl Documentation Perl::Critic::Policy::BuiltinFunctions::ProhibitUniversalCan(3pm)

NAME

Perl::Critic::Policy::BuiltinFunctions::ProhibitUniversalCan - Write "eval { $foo->can($name) }" instead of "UNIVERSAL::can($foo, $name)".

AFFILIATION

This Policy is part of the core Perl::Critic distribution.

DESCRIPTION

    print UNIVERSAL::can($obj, 'Foo::Bar') ? 'yes' : 'no';  #not ok
    print eval { $obj->can('Foo::Bar') } ? 'yes' : 'no';    #ok

As of Perl 5.9.3, the use of UNIVERSAL::can as a function has been deprecated and the method form is preferred instead. Formerly, the functional form was recommended because it gave valid results even when the object was "undef" or an unblessed scalar. However, the functional form makes it impossible for packages to override can(), a technique which is crucial for implementing mock objects and some facades.

See UNIVERSAL::can for a more thorough discussion of this topic.

CONFIGURATION

This Policy is not configurable except for the standard options.

SEE ALSO

Perl::Critic::Policy::BuiltinFunctions::ProhibitUniversalIsa

AUTHOR

Chris Dolan <cdolan@cpan.org>

COPYRIGHT

Copyright (c) 2006-2023 Chris Dolan.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of this license can be found in the LICENSE file included with this module.

2024-03-08 perl v5.38.2