Merge pull request #5 from misfo/module_with

Separate method selection from including/extending

README.md

@@ -24,10 +24,8 @@ module Statistics
 end
 
 class Main
-  include Rns
-
-  extend_specified Arithmetic => [:inc]
-  include_specified Statistics => [:avg]
+  extend Rns.module_with(Arithmetic => [:inc])
+  include Rns.module_with(Statistics => [:avg])
 
   def main
     puts "1+1 is #{self.class.inc 1} and the average of [1,2,3] is #{avg [1,2,3]}"

lib/rns.rb

@@ -1,8 +1,4 @@
 module Rns
-  def self.included(base)
-    base.extend(ClassMethods)
-  end
-
   class << self
     def f(m)
       lambda{|*args| send(m, *args)}
@@ -42,6 +38,10 @@ def constant_for(module_names)
       more.reduce(Kernel.const_get(m)){|m, s| m.const_get(s)}
     end
 
+    def module_with(use_spec)
+      Module.new.tap {|m| add_methods(m, use_spec) }
+    end
+
     def add_methods(to, use_spec)
       use_spec.to_a.each do |from, sub_spec|
         if (sub_spec.is_a? Hash)
@@ -64,17 +64,6 @@ def add_methods(to, use_spec)
     end
   end
 
-  module ClassMethods
-    def include_specified(use_spec)
-      Rns::add_methods(self, use_spec)
-    end
-
-    def extend_specified(use_spec)
-      singleton_class = class << self; self; end
-      Rns::add_methods(singleton_class, use_spec)
-    end
-  end
-
   def self.using(use_spec, &blk)
     blk[Object.new.tap{|o| Rns::add_methods(o.class, use_spec)}]
   end

spec/rns/rns_spec.rb

@@ -19,11 +19,10 @@ def self.avg(arr); arr.reduce(:+).to_f / arr.count end
   end
 end
 
-class Thing
-  include Rns
 
-  extend_specified Math::Arithmetic => [:inc]
-  include_specified Math::Statistics => [:avg]
+class Thing
+  extend Rns.module_with(Math::Arithmetic => [:inc])
+  include Rns.module_with(Math::Statistics => [:avg])
 
   def inced_one
     self.class.inc 1