/usr/local/perl/lib/site_perl/5.8.5/Perl/Critic/Policy/BuiltinFunctions/ProhibitUniversalIsa.pm |
Perl::Critic::Policy::BuiltinFunctions::ProhibitUniversalIsa
print UNIVERSAL::isa($obj, 'Foo::Bar') ? 'yes' : 'no'; #not ok print eval { $obj->isa('Foo::Bar') } ? 'yes' : 'no'; #ok
As of Perl 5.9.3, the use of UNIVERSAL::isa
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 isa()
,
a technique which is crucial for implementing mock objects and some
facades.
Another alternative to UNIVERSAL::isa is the _INSTANCE
method of
Param::Util, which is faster.
See the CPAN module the UNIVERSAL::isa manpage for an incendiary discussion of this topic.
the Perl::Critic::Policy::BuiltinFunctions::ProhibitUniversalCan manpage
Chris Dolan <cdolan@cpan.org>
Copyright (c) 2006 Chris Dolan. All rights reserved.
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.
/usr/local/perl/lib/site_perl/5.8.5/Perl/Critic/Policy/BuiltinFunctions/ProhibitUniversalIsa.pm |