add derivation possibility to class definition

lib/parser/module_definition.rb

@@ -7,7 +7,7 @@ module Parser
     end
 
     rule(:class_definition) do
-      keyword_class >> module_name >> eol >>
+      keyword_class >> module_name >> (smaller >> module_name).maybe.as(:derived_name) >> eol >>
       ( (keyword_end.absent? >> root_body).repeat()).as(:class_expressions) >> keyword_end >> newline
     end
 

lib/parser/transform.rb

@@ -72,8 +72,8 @@ module Parser
     rule( :module_name => simple(:module_name) , :module_expressions => sequence(:module_expressions) , :end=>"end") do
       Ast::ModuleExpression.new(module_name , module_expressions)
     end
-    rule( :module_name => simple(:module_name) , :class_expressions => sequence(:class_expressions) , :end=>"end") do
-      Ast::ClassExpression.new(module_name , class_expressions)
+    rule( :module_name => simple(:module_name) , :derived_name => simple(:derived_name) , :class_expressions => sequence(:class_expressions) , :end=>"end") do
+      Ast::ClassExpression.new(module_name , derived_name ? derived_name.name : nil , class_expressions)
     end
     
     #shortcut to get the ast tree for a given string