introduce goto instead of using machines jump

fix labels so compiler does not return duplicates

lib/slot_language/code/resolve_method.slot

@@ -2,7 +2,7 @@
 word! = name_
 cache_entry! = cache_entry_
 # local var assignment
-callable_method = cache_entry.cached_type.methods
+callable_method! = cache_entry.cached_type.methods
 
 while_start_label
 

lib/slot_language/goto.rb

@@ -0,0 +1,10 @@
+module SlotLanguage
+  class Goto
+    attr_reader :label
+
+    def initialize(label)
+      @label = label
+    end
+
+  end
+end

lib/slot_language/slot_compiler.rb

@@ -10,6 +10,10 @@ module SlotLanguage
       self.new.process(ast)
     end
 
+    def initialize
+      @labels = {}
+    end
+
     def not_implemented(node)
       raise "Not implemented #{node.type}"
     end
@@ -60,13 +64,18 @@ module SlotLanguage
 
     private
     def label(name)
-      SlotMachine::Label.new(name.to_s , name)
+      raise "no label #{name}" unless(name.to_s.end_with?("_label"))
+      if @labels.has_key?(name)
+        return @labels[name]
+      else
+        @labels[name] = SlotMachine::Label.new(name.to_s , name)
+      end
     end
     def goto(name , args)
       # error handling would not hurt
       puts "goto #{name} , #{args}" if DEBUG
       label = process(args.first)
-      SlotMachine::Jump.new(  label )
+      Goto.new(  label )
     end
     def check(name , receiver , kids)
       raise "Only ==, not #{name}" unless name == :==
@@ -90,3 +99,4 @@ require_relative "slot_maker"
 require_relative "load_maker"
 require_relative "check_maker"
 require_relative "macro_maker"
+require_relative "goto"

test/slot_language/test_goto.rb

@@ -0,0 +1,36 @@
+require_relative "helper"
+
+module SlotLanguage
+  class TestGoto < MiniTest::Test
+    include SlotHelper
+
+    def test_goto_class
+      assert_equal Goto , compile_class("goto(exit_label)")
+    end
+    def test_goto_label
+      goto = compile("goto(exit_label)")
+      assert_equal SlotMachine::Label , goto.label.class
+      assert_equal :exit_label , goto.label.name
+    end
+
+    def test_label
+      label = compile("while_label")
+      assert_equal SlotMachine::Label , label.class
+      assert_equal :while_label , label.name
+    end
+
+    def test_2_label
+      labels = compile("exit_label;exit_label")
+      assert_equal :exit_label , labels[0].name
+      assert_equal :exit_label , labels[1].name
+      assert_equal labels[0].object_id , labels[1].object_id
+    end
+
+    def test_goto_with_label
+      gotos = compile("exit_label;goto(exit_label)")
+      assert_equal :exit_label , gotos[0].name
+      assert_equal :exit_label , gotos[1].label.name
+      assert_equal gotos[0].object_id , gotos[1].label.object_id
+    end
+  end
+end

test/slot_language/test_slot_compiler.rb

@@ -10,11 +10,6 @@ module SlotLanguage
     def test_compile
       assert_equal SlotMaker , compile("a").class
     end
-    def test_label
-      label = compile("while_label")
-      assert_equal SlotMachine::Label , label.class
-      assert_equal :while_label , label.name
-    end
     def test_slot_load_rinst
       assert_equal LoadMaker , compile_class("a = @b")
     end
@@ -30,13 +25,10 @@ module SlotLanguage
     def test_slot_load_linst_trav2
        assert_equal LoadMaker , compile_class("@a.c = b.c")
     end
-    def test_goto
-      assert_equal SlotMachine::Jump , compile_class("goto(exit_label)")
-    end
     def test_if
       check = compile("goto(exit_label) if(a == b)")
       assert_equal CheckMaker , check.class
-      assert_equal SlotMachine::Jump , check.goto.class
+      assert_equal Goto , check.goto.class
     end
     def test_assign
       assign = compile("c = d")
@@ -54,7 +46,7 @@ module SlotLanguage
       multi = compile("start_label;c = c.next;goto(start_label)")
       assert_equal Array , multi.class
       assert_equal SlotMachine::Label , multi.first.class
-      assert_equal SlotMachine::Jump , multi.last.class
+      assert_equal Goto , multi.last.class
     end
     def test_shift
       load = compile("word = name.member")