remove Data2 in favour of Data4

as we write a Marker, type and marker make up 2
so data2 is just the type, not useful

lib/parfait/data_object.rb

@@ -13,8 +13,8 @@
 # logical and math operation that are bundled into the OperatorInstruction.
 #
 # For safe access the access code needs to know the length of the data, which is
-# encoded in the class/type name. Ie An Integer derives from Data2, which is 2 long
-# (minus one for the type, so exactly the one word for the integer)
+# encoded in the class/type name. Ie An Integer derives from Data4, which is 4 long
+# ( one for the type, one for the next, one word for the integer and currently still a marker)
 #
 # DataObjects still have a type, and so can have objects before the data starts
 #
@@ -44,9 +44,9 @@ module Parfait
     end
   end
 
-  class Data2 < DataObject
+  class Data4 < DataObject
     def data_length
-      1
+      3
     end
     def padded_length
       2 * 4

lib/parfait/integer.rb

@@ -7,15 +7,18 @@
 # Ie it would be possible to change the value, we just don't support that)
 
 module Parfait
-  class Integer < Data2
+  class Integer < Data4
 
-    #FIXME: this is "just" for compilation
-    def initialize(value)
+    def initialize(value , next_i = nil)
       super()
       @value = value
+      @next_i = next_i
     end
-    attr_reader :value
+    attr_reader :next_i, :value
 
+    def self.integer_index
+      3 # 1 type, 2 next_i
+    end
     # :integer?, :odd?, :even?, :upto, :downto, :times, :succ, :next, :pred, :chr, :ord, :to_i, :to_int, :floor,
     # :ceil, :truncate, :round, :gcd, :lcm, :gcdlcm, :numerator, :denominator, :to_r, :rationalize,
     # :singleton_method_added, :coerce, :i, :+@, :-@, :fdiv, :div, :divmod, :%, :modulo, :remainder, :abs, :magnitude,
@@ -30,19 +33,19 @@ module Parfait
   end
 
   # adding other base classes in here for now:
-  class FalseClass < Data2
+  class FalseClass < Data4
     #FIXME: this is "just" for compilation
     def initialize
       super
     end
   end
-  class TrueClass < Data2
+  class TrueClass < Data4
     #FIXME: this is "just" for compilation
     def initialize
       super
     end
   end
-  class NilClass < Data2
+  class NilClass < Data4
     #FIXME: this is "just" for compilation
     def initialize
       super