first steps to defining specialised slot classes

getting rid of the mess in SlotDefinition (wip)

lib/slot_language/slot_maker.rb

@@ -18,7 +18,7 @@ module SlotLanguage
     end
 
     def slot_def(compiler)
-      SlotMachine::SlotDefinition.new(:message , leaps)
+      SlotMachine::SlotDefinition.for(:message , leaps)
     end
 
     def to_s

lib/slot_machine/instruction/message_definition.rb

@@ -0,0 +1,29 @@
+module SlotMachine
+  class MessageDefinition < SlotDefinition
+
+    def initialize(slots)
+      super(:message , slots)
+    end
+
+    def known_name
+      known_object
+    end
+
+    # load the slots into a register
+    # the code is added to compiler
+    # the register returned
+    def to_register(compiler, source)
+      type = :Message
+      right = compiler.use_reg( type )
+      slots = @slots.dup
+      left = Risc.message_reg
+      left = left.resolve_and_add( slots.shift , compiler)
+      reg = compiler.current.register
+      while( !slots.empty? )
+        left = left.resolve_and_add( slots.shift , compiler)
+      end
+      return reg
+    end
+
+  end
+end

lib/slot_machine/instruction/slot_definition.rb

@@ -1,7 +1,7 @@
 module SlotMachine
   # A SlotDefinition defines a slot. A bit like a variable name but for objects.
   #
-  # PS: for the interested: A "developement" of Smalltalk was the
+  # PS: for the interested: A "development" of Smalltalk was the
   #     prototype based language (read: JavaScript equivalent)
   #     called Self https://en.wikipedia.org/wiki/Self_(programming_language)
   #
@@ -15,6 +15,16 @@ module SlotMachine
   # Instructions. Or in the case of constants to ConstantLoad
   #
   class SlotDefinition
+    # get the right definition, depending on the object
+    def self.for(object , slots)
+      case object
+      when :message
+        MessageDefinition.new(slots)
+      else
+        SlotDefinition.new(object,slots)
+      end
+    end
+
     attr_reader :known_object , :slots
     # is an array of symbols, that specifies the first the object, and then the Slot.
     # The first element is either a known type name (Capitalized symbol of the class name) ,
@@ -39,8 +49,6 @@ module SlotMachine
         known_object.class.short_name
       when Risc::Label
         known_object.to_s
-      when Symbol
-        known_object
       else
         "unknown"
       end
@@ -69,14 +77,12 @@ module SlotMachine
         end
         raise "Can't have slots into Constants #{slots}" if slots.length > 1
       when Parfait::Object , Risc::Label
-        const = const  = Risc.load_constant(source, known_object , right)
+        const = Risc.load_constant(source, known_object , right)
         compiler.add_code const
         if slots.length > 0
           # desctructively replace the existing value to be loaded if more slots
           compiler.add_code Risc.slot_to_reg( source , right ,slots[0], right)
         end
-      when Symbol
-        return sym_to_risc(compiler , source)
       else
         raise "We have a #{self} #{known_object}"
       end
@@ -92,19 +98,5 @@ module SlotMachine
       return const.register
     end
 
-    # resolve the slots one by one to slot_to_reg instructions using the
-    # type information inferred from their names / type hierachy
-    def sym_to_risc(compiler , source)
-      slots = @slots.dup
-      raise "Not Message #{@known_object}" unless @known_object == :message
-      left = Risc.message_reg
-      left = left.resolve_and_add( slots.shift , compiler)
-      reg = compiler.current.register
-      while( !slots.empty? )
-        left = left.resolve_and_add( slots.shift , compiler)
-      end
-      return reg
-    end
-
   end
 end

lib/slot_machine/instruction/slot_load.rb

@@ -31,8 +31,8 @@ module SlotMachine
     def initialize(source , left , right, original_source = nil)
       super(source)
       @left , @right = left , right
-      @left = SlotDefinition.new(@left.shift , @left) if @left.is_a? Array
-      @right = SlotDefinition.new(@right.shift , @right) if @right.is_a? Array
+      @left = SlotDefinition.for(@left.shift , @left) if @left.is_a? Array
+      @right = SlotDefinition.for(@right.shift , @right) if @right.is_a? Array
       raise "right not SlotMachine, #{@right.to_s}" unless @right.is_a?( SlotDefinition )
       @original_source = original_source || self
     end
@@ -81,3 +81,4 @@ module SlotMachine
 
 end
 require_relative "slot_definition"
+require_relative "message_definition"

lib/sol/assignment.rb

@@ -32,7 +32,7 @@ module Sol
     #
     # Derived classes do not implement to_slot, only slot_position
     def to_slot(compiler)
-      to = SlotMachine::SlotDefinition.new(:message , self.slot_position(compiler))
+      to = SlotMachine::SlotDefinition.for(:message , self.slot_position(compiler))
       from = @value.to_slot_definition(compiler)
       assign = SlotMachine::SlotLoad.new(self,to,from)
       return assign unless @value.is_a?(CallStatement)

lib/sol/basic_values.rb

@@ -10,7 +10,7 @@ module Sol
       @value = value
     end
     def to_slot_definition(_)
-      return SlotMachine::SlotDefinition.new(SlotMachine::IntegerConstant.new(@value) , [])
+      return SlotMachine::SlotDefinition.for(SlotMachine::IntegerConstant.new(@value) , [])
     end
     def ct_type
       Parfait.object_space.get_type_by_class_name(:Integer)
@@ -38,7 +38,7 @@ module Sol
       Parfait.object_space.get_type_by_class_name(:True)
     end
     def to_slot_definition(_)
-      return SlotMachine::SlotDefinition.new(Parfait.object_space.true_object , [])
+      return SlotMachine::SlotDefinition.for(Parfait.object_space.true_object , [])
     end
     def to_s(depth = 0)
       "true"
@@ -50,7 +50,7 @@ module Sol
       Parfait.object_space.get_type_by_class_name(:False)
     end
     def to_slot_definition(_)
-      return SlotMachine::SlotDefinition.new(Parfait.object_space.false_object , [])
+      return SlotMachine::SlotDefinition.for(Parfait.object_space.false_object , [])
     end
     def to_s(depth = 0)
       "false"
@@ -62,7 +62,7 @@ module Sol
       Parfait.object_space.get_type_by_class_name(:Nil)
     end
     def to_slot_definition(_)
-      return SlotMachine::SlotDefinition.new(Parfait.object_space.nil_object , [])
+      return SlotMachine::SlotDefinition.for(Parfait.object_space.nil_object , [])
     end
     def to_s(depth = 0)
       "nil"
@@ -77,7 +77,7 @@ module Sol
     end
     def to_slot_definition(compiler)
       @my_type = compiler.receiver_type
-      SlotMachine::SlotDefinition.new(:message , [:receiver])
+      SlotMachine::SlotDefinition.for(:message , [:receiver])
     end
     def ct_type
       @my_type
@@ -92,7 +92,7 @@ module Sol
       @value = value
     end
     def to_slot_definition(_)
-      return SlotMachine::SlotDefinition.new(SlotMachine::StringConstant.new(@value),[])
+      return SlotMachine::SlotDefinition.for(SlotMachine::StringConstant.new(@value),[])
     end
     def ct_type
       Parfait.object_space.get_type_by_class_name(:Word)

lib/sol/call_statement.rb

@@ -11,7 +11,7 @@ module Sol
     # When used as right hand side, this tells what data to move to get the result into
     # a varaible. It is (off course) the return value of the message
     def to_slot_definition(_)
-      SlotMachine::SlotDefinition.new(:message ,[ :return_value])
+      SlotMachine::SlotDefinition.for(:message ,[ :return_value])
     end
 
     def to_s(depth = 0)

lib/sol/lambda_expression.rb

@@ -15,7 +15,7 @@ module Sol
     # fact never called)
     def to_slot_definition(compiler)
       compile(compiler) unless @parfait_block
-      return SlotMachine::SlotDefinition.new(SlotMachine::LambdaConstant.new(parfait_block(compiler)) , [])
+      return SlotMachine::SlotDefinition.for(SlotMachine::LambdaConstant.new(parfait_block(compiler)) , [])
     end
 
     # create a block, a compiler for it, compile the block and add the compiler(code)

lib/sol/macro_expression.rb

@@ -15,7 +15,7 @@ module Sol
     # When used as right hand side, this tells what data to move to get the result into
     # a varaible. It is (off course) the return value of the message
     def to_slot_definition(_)
-      SlotMachine::SlotDefinition.new(:message ,[ :return_value])
+      SlotMachine::SlotDefinition.for(:message ,[ :return_value])
     end
 
     def to_s(depth = 0)

lib/sol/send_statement.rb

@@ -116,7 +116,7 @@ module Sol
       defi
     end
     def build_condition(ok_label, compiler)
-      cached_type = SlotMachine::SlotDefinition.new(dynamic_call.cache_entry , [:cached_type])
+      cached_type = SlotMachine::SlotDefinition.for(dynamic_call.cache_entry , [:cached_type])
       current_type = receiver_type_definition(compiler)
       SlotMachine::NotSameCheck.new(cached_type , current_type, ok_label)
     end

lib/sol/variables.rb

@@ -12,7 +12,7 @@ module Sol
     include Named
     def to_slot_definition(compiler)
       slot_def = compiler.slot_type_for(@name)
-      SlotMachine::SlotDefinition.new(:message , slot_def)
+      SlotMachine::SlotDefinition.for(:message , slot_def)
     end
     def to_s(depth = 0)
       name.to_s
@@ -25,7 +25,7 @@ module Sol
   class InstanceVariable < Expression
     include Named
     def to_slot_definition(_)
-      SlotMachine::SlotDefinition.new(:message , [ :receiver , @name] )
+      SlotMachine::SlotDefinition.for(:message , [ :receiver , @name] )
     end
     # used to collect type information
     def add_ivar( array )
@@ -52,7 +52,7 @@ module Sol
       get_named_class.single_class.instance_type
     end
     def to_slot_definition(_)
-      return SlotMachine::SlotDefinition.new( get_named_class, [])
+      return SlotMachine::SlotDefinition.for( get_named_class, [])
     end
     def get_named_class
       Parfait.object_space.get_class_by_name(self.name)

lib/sol/yield_statement.rb

@@ -34,8 +34,8 @@ module Sol
     #      we brace ourselves with the check, and exit (later raise) if . . .
     def method_check(compiler)
       ok_label = SlotMachine::Label.new(self,"method_ok_#{self.object_id}")
-      compile_method = SlotMachine::SlotDefinition.new( compiler.get_method , [])
-      runtime_method = SlotMachine::SlotDefinition.new( :message , [ :method] )
+      compile_method = SlotMachine::SlotDefinition.for( compiler.get_method , [])
+      runtime_method = SlotMachine::SlotDefinition.for( :message , [ :method] )
       check = SlotMachine::NotSameCheck.new(compile_method , runtime_method, ok_label)
       # TODO? Maybe create slot instructions for this
       #builder = compiler.builder("yield")