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Postings from March 2007
On Sunday 11 March 2007 05:45, demerphq wrote: > I have fixed this problem by making UNIVERSAL::DOES($item,$role) when > used in subroutine form work in DWIM fashion. When $item is an > unblessed reference, then it delegates to UNIVERSAL::isa() via > subroutine call. I support the idea of making ->DOES() work on internal "types" (ARRAY, REGEX, CODE, etc), but I think this idea is wrong. 1) ->DOES() is a method on purpose, for overridability purposes. 2) Things that are methods should look like methods -- not just for clarity of that feature's purpose, but to avoid confusion between other features. For example, UNIVERSAL::isa() and UNIVERSAL::can() are still methods and not functions, and the documentation finally expresses that. Adding yet another "is it a method or is it a function" confuses the issue yet again (and anyone who wants to maintain a whole pile of bug-free code that people using methods as functions carelessly in distributions such as Template Toolkit and DBI::Class is more than welcome). 3) Hiding method calls underneath function calls is a well-established practice in Perl 5 -- you can see it in such clean and easily maintained code as the magic system. Adding a new feature to the core by the way of a hack seems to go against good design principles. 4) ->DOES() works as a class method as well as an instance method. Delegating based on the blessedness of the invocant breaks this if the class has overridden DOES(). I believe the right approach to making ->DOES() work on built-in types is through autobox. An alternate approach is to add a does() built-in, like ref() but actually useful. -- cThread Previous | Thread Next