lib/patternmatching/pattern.rb in patternmatching-0.1.4 vs lib/patternmatching/pattern.rb in patternmatching-0.2.0

@@ -115,37 +115,50 @@
         begin
           Collector.walk(source, target, args)
         rescue NotMatched
           next
         end
-        return ExecuteAs.new(args, receiver).call(&action)
+        return ExecuteAs.new(args, receiver).instance_eval(&action)
       end      
     end
     
+    # Private class to access instance valiables of the receiver
+    class InstanceVariableAccessor
+      def initialize(receiver)
+        @receiver = receiver
+      end
+      def method_missing(name, *args)
+        begin
+          @receiver.send(name, *args)
+        rescue NameError
+          if name.to_s[-1,1] == "="
+            field = "@" + name.to_s[0...-1]
+            @receiver.instance_variable_set(field, args[0])
+          else
+            field = "@" + name.to_s
+            @receiver.instance_variable_get(field, args[0])
+          end
+        end
+      end
+    end
+    
     #Private class enabling to use the name of symbols in patterns 
     #like a local variables in action blocks
     class ExecuteAs
       def initialize(args, receiver)
-        @this = receiver
+        @receiver = receiver
+        @wrapper = InstanceVariableAccessor.new receiver
         @args = args
       end
-      def call(&action)
-        args = @args
-        mod = Module.new
-        mod.instance_eval do
-          define_method(:method_missing) do |name, *margs|
-            return args[name] if args.key?(name)
-            super(name, *margs)
-          end
-        end
-        # this block is not thread safe
-        @this.extend mod
-        result = @this.instance_eval(&action)
-        mod.instance_eval do
-          remove_method(:method_missing)
-        end
-        # 
-        result
+      def this
+        @receiver
+      end
+      def the
+        @wrapper
+      end
+      def method_missing(name, *args)
+        return @args[name] if @args.key?(name)
+        @receiver.send(name, *args)
       end
     end
   end
   
   #Private class for collecting pattern/action fragments