gets the if coded, but test fail die to instruction being a graph now

lib/virtual/instruction.rb

@@ -24,14 +24,45 @@ module Virtual
   # an implementation (in a programm it would be a function). But in a virtual machine, not only do we need this instruction,
   # it is indeed the first instruction as just this instruction is the smallest possible programm for the machine.
   # As such it is the next instruction for any first instruction that we generate.
-  class Halt < Instruction 
-    
+  class Halt < Instruction    
   end
 
   # following classes are stubs. currently in brainstorming mode, so anything may change anytime
-  class MethodDefinitionEnter < Instruction
+  class MethodEnter < Instruction
   end
 
+  #resolves to nothing, but allows forward definition
+  class Label < Instruction
+  end
+
+  # the next instruction represents the true branch and the other is the .... other
+  # could have been the false, but false is a keyword and is asymetric to next anyway
+  # this is an abstract base class (though no measures are taken to prevent instantiation) and derived
+  # class names indicate the actual test
+  class Branch < Instruction
+    def initialize nex = nil , other = nil
+      super(nex)
+      @other = other
+    end
+    attr_reader :other
+    def attributes
+      [:other] + super
+    end
+    # so code can be "poured in" in the same way as normal, we swap the braches around in after the true condition
+    # and swap them back after
+    def swap
+      tmp = @other
+      @other = @next
+      @next = tmp
+    end
+  end
+
+  # implicit means there is no explcit test involved.
+  # normal ruby rules are false and nil are false, EVERYTHING else is true (and that includes 0)
+  class ImplicitBranch < Branch
+  end
+
+  # A note: future branch conditions include OverflowBranch and other non-c 
   class FrameGet < Instruction
     def initialize name , nex = nil
       super(nex)