Subject: | UNIVERSAL::isa does not support undef |
UNIVERSAL::isa (the function) supports undef, returning false.
UNIVERSAL::isa (the class) breaks any code that takes advantage of this.
is( scalar(UNIVERSAL::isa(undef, 'Foo')), undef, 'isa on undef returns undef');
require UNIVERSAL::isa;
is( scalar(UNIVERSAL::isa(undef, 'Foo')), undef, 'isa on undef returns undef');