The proposed Ruby Package Standard states:

  File names and directory structure SHOULD correspond like this:

    Library: foo-bar
    Directory: lib/foo/bar
    Namespace: Foo::Bar

    Library: foo_bar
    Directory: lib/foo_bar
    Namespace: FooBar

That being the case I think Ruby needs to include methods to make it
easy to translate between these. In ActiveSupport these methods are
String#pathize and String#methodize. I would think there would also be
something like String#modulize.

Without such methods I think it is a bit much to ask of developers to
keep this correspondence. I have code that needs to do such
translations dynamically and because Ruby does not have such methods,
I used a FooBar -> foobar.rb correspondence instead (easily
transformed via #downcase). A fact that has led me to generally use
this correspondence throughout all my projects.

I'm all for the proposed standard, but Ruby needs to support it too.