On Jan 12, 3:45 pm, "Per Velschow" <Per.Velsc... / gmail.com> wrote:
> > This is interesting. Does Ruby allow codeless methods in a module like
> > those of an java interface?That wouldn't make sense. The only reason for having methods defined
> with no code is when you have static type checking as in Java. In Ruby
> everything happens at run-time.

However, this is much more powerful, because it allows you to reference
methods in your modules that you
expect classes to implement.

For example,  all you need is <=> to get all of Comparable, and #each
to get Enumerable.

Designing with this in mind can be *very* powerful