add also calls on classes and more tests for that

lib/ast/call_site_expression.rb

@@ -2,10 +2,12 @@ module Ast
   # assignment, like operators are really function calls
   
   class CallSiteExpression < Expression
-    attr_reader  :name, :args
-    def initialize name, args
-      @name , @args = name.to_sym , args
+    attr_reader  :name, :args , :receiver
+
+    def initialize name, args , receiver = Ast::NameExpression.new("self")
+      @name , @args , @receiver = name.to_sym , args , receiver
     end
+
     def compile context , into
       params = args.collect{ |a| a.compile(context, into) }
       #TOOD, this needs dynamic resolution
@@ -23,13 +25,13 @@ module Ast
 
     def inspect
       self.class.name + ".new(" + name.inspect + ", ["+ 
-        args.collect{|m| m.inspect }.join( ",") +"] )"  
+        args.collect{|m| m.inspect }.join( ",") + "] ," + receiver.inspect  + ")"  
     end
     def to_s
       "#{name}(" + args.join(",") + ")"
     end
     def attributes
-      [:name , :args]
+      [:name , :args , :receiver]
     end
   end