refactored the SlotLoad into SlotDefs

That sort of removes the last horrible code.
Surely can still be improved, but mostly oo now

lib/slot_machine/instruction/object_definition.rb

@@ -1,20 +1,6 @@
 module SlotMachine
   class ObjectDefinition < SlotDefinition
 
-    # get the right definition, depending on the object
-    def self.for(object , slots)
-      case object
-      when :message
-        MessageDefinition.new(slots)
-      when Constant
-        ConstantDefinition.new(object , slots)
-      when Parfait::Object
-        ObjectDefinition.new(object , slots)
-      else
-        SlotDefinition.new(object,slots)
-      end
-    end
-
     def initialize( object , slots)
       super(object , slots )
     end
@@ -47,5 +33,14 @@ module SlotMachine
       return const.register
     end
 
+    # Note: this is the left hand case, the right hand being to_register
+    #       They are very similar (apart from the final reg_to_slot here) and should
+    #       most likely be united
+    def reduce_and_load(const_reg , compiler , original_source )
+      raise "only cache" unless known_object.is_a?( Parfait::CacheEntry)
+      left = compiler.use_reg( :CacheEntry )
+      compiler.add_code Risc.load_constant(original_source, known_object , left)
+      compiler.add_code Risc.reg_to_slot(original_source, const_reg , left, slots.first)
+    end
   end
 end