lib/rext/module/helpers.rb in visionmedia-rext-0.0.8 vs lib/rext/module/helpers.rb in visionmedia-rext-0.1.0

@@ -6,6 +6,48 @@
   
   def chain &block
     include Module.new(&block)
   end
   
+  ##
+  # Call +method+ when conditions are met.
+  #
+  # This method provides a simple means of 
+  # utilizing method_missing, and should
+  # be used in most cases.
+  #
+  # When using a regular expression with
+  # the :if option, all captures are passed
+  # to the handling method.
+  #
+  # === Examples
+  #    
+  #   class Foo
+  #     call_method :find_by, :if => /^find_by_(\w+)/
+  #     def find_by attr, *args
+  #       "finding by #{attr} with #{args.join(', ')}"
+  #     end
+  #   end
+  #
+  #   foo = Foo.new
+  #   foo.find_by_name('bar') # => "finding by name with bar"
+  #
+  # === Options
+  #
+  #   :if   regexp or proc
+  #
+  
+  def call_method method, options = {}
+    chain {
+      define_method :method_missing do |meth, *args|
+        if options[:if].is_a?(Regexp) && meth.to_s =~ options[:if]
+          send method, *($~.captures + args)
+        elsif options[:if].respond_to?(:call) && options[:if].call(meth, *args)
+          send method, *args
+        else
+          super
+        end
+      end
+    }
+  end
+  
 end
\ No newline at end of file