Problem

You want to define an abstract method that must be defined by a subclass or will throw an exception if used.

Solution

Use Abstract#method (defined below) and add the following call inside the definition of your class:

Abstract.method(:method_name)

Discussion

#!/usr/local/bin/ruby -w

FIX: make dynamic code. IO problems in RubyCodeRenderer prevent this.

module Abstract def Abstract.method(name, *args) code = “def #{name}(#{args}) raise "#{self.class}##{name} is abstract. Definition is a subclass responsibility." end” self.module_eval(code) end end

class Abstractclass include Abstract Abstract.method(:foo) end

class Concreteclass < Abstractclass def foo puts “Yeah!” end end

c = Concreteclass.new c.foo

c = Abstractclass.new c.foo

Contrast

TODO: CONTRAST

Related

TODO: LIST_OF_RELATED_ITEMS

Status: In Progress