fix while back jump

while normalising the condition had gone before the
jump target accidentally

lib/vool/statements/while_statement.rb

@@ -3,33 +3,34 @@ require_relative "normalizer"
 module Vool
   class WhileStatement < Statement
     include Normalizer
-    attr_reader :condition , :body
+    attr_reader :condition , :body , :hoisted
 
-    def initialize( condition , body )
+    def initialize( condition , body , hoisted = nil)
+      @hoisted = hoisted
       @condition = condition
       @body = body
     end
 
     def normalize
       cond , rest = *normalize_name(@condition)
-      me = WhileStatement.new(cond , @body.normalize)
-      return me unless rest
-      rest << me
-      rest
+      WhileStatement.new(cond , @body.normalize , rest)
     end
 
     def to_mom( method )
       merge_label = Mom::Label.new( "merge_label_#{object_id}")
       cond_label = Mom::Label.new( "cond_label_#{object_id}")
-      cond_label << Mom::TruthCheck.new(condition.slot_definition(method) , merge_label)
-      cond_label << @body.to_mom(method)
-      cond_label << Mom::Jump.new(cond_label)
-      cond_label << merge_label
+      codes = cond_label
+      codes << @hoisted.to_mom(method) if @hoisted
+      codes << Mom::TruthCheck.new(condition.slot_definition(method) , merge_label)
+      codes << @body.to_mom(method)
+      codes << Mom::Jump.new(cond_label)
+      codes << merge_label
     end
 
     def each(&block)
       block.call(self)
       block.call(@condition)
+      @hoisted.each(&block) if @hoisted
       @body.each(&block)
     end