lib/immutable.rb in up_the_irons-immutable-0.1 vs lib/immutable.rb in up_the_irons-immutable-0.2

@@ -1,31 +1,35 @@
 module Immutable
+  class CannotOverrideMethod < StandardError; end
+
   def self.included(mod)
     mod.extend(ClassMethods)
   end
 
   module ClassMethods
     def immutable_method(*args)
+      opts = args.last.is_a?(Hash) ? args.pop : {}
+      
       args.each do |method|
         alias_method "orig_#{method}", method
       end
 
-      @args = args
+      @args = args; @opts = opts
       module_eval do
         def self.method_added(sym)
           if @args
             @args.each do |method|
-              if method
-                if sym == method.to_sym 
-                  unless called_by_method_added
-                    self.module_eval <<-"end;"
-                      def #{method.to_s}(*args, &block)
-                        orig_#{method.to_s}(*args, &block)
-                      end
-                    end;
-                  end # called_by_method_added
-                end # method.to_sym
-              end # method
+              if method && sym == method.to_sym && !called_by_method_added
+                unless @opts[:silent]
+                  raise CannotOverrideMethod, "Cannot override the immutable method: #{sym}"
+                end
+
+                self.module_eval <<-"end;"
+                  def #{method.to_s}(*args, &block)
+                    orig_#{method.to_s}(*args, &block)
+                  end
+                end;
+              end 
             end # @args.each
           end # @args
         end # def self.method_added()
 
         def self.method_undefined(sym)