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

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

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

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.

This Policy is not configurable except for the standard options.

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

Chris Dolan <cdolan@cpan.org>

Copyright (c) 2006-2011 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.

2023-07-26 perl v5.38.0