thanks a lot for those remarks and pointers! kind regards robert "Paul Brannan" <pbrannan / atdesk.com> schrieb im Newsbeitrag news:20030102160633.GS31857 / atdesk.com... > On Thu, Jan 02, 2003 at 11:49:55PM +0900, Robert wrote: > > since ruby is dynamically type in principle there is no technical need for > > interfaces. however, if i want to define an interface - say for reasons of > > documentation - what is the suggested way to do so? create a class with a > > set of methods returning 'nil' or 'self'? or create a method, that checks > > the interface of an instance and raises a TypeError if any of the methods is > > missing? what would you suggest? > > Make sure whatever mechanism you use is a module and not a class. Ruby > only has single inheritance, so if it's a class, then I can't get both > your interface and inherit from another class. > > See some discussion on this at (at the bottom under Abstract Base > Classes): > > http://www.rubygarden.org/ruby?RubyFromCpp > > See also an earlier thread on this list starting at [ruby-talk:53297]. > > Paul > >