     end
 
     test "increment and decrement" do
-      assert RPNForthThing.initialize(~w[ 3 ++ ]) == 4
-      assert RPNForthThing.initialize(~w[ 3 -- ]) == 2
+      assert RPNForthThing.initialize(~w[ 3 1+ ]) == 4
+      assert RPNForthThing.initialize(~w[ 3 1- ]) == 2
     end
 
     test "unary negation" do
       assert RPNForthThing.initialize(~w[ -3 @- ]) == 3
     end
 
-    test "if ? then else" do
-      assert RPNForthThing.initialize(~w[ 3 5 < if 33 44 ]) == 33
-      assert RPNForthThing.initialize(~w[ 3 5 < ? 33 44 ]) == 33
-      assert RPNForthThing.initialize(~w[ 3 5 > if 33 44 ]) == 44
-      assert RPNForthThing.initialize(~w[ 3 5 > ? 33 44 ]) == 44
+    test "if else then" do
+      assert RPNForthThing.initialize(~w[ 3 5 < if 33 else 44 then ]) == 33
+      # assert RPNForthThing.initialize(~w[ 3 5 < ? 33 44 ]) == 33
+      assert RPNForthThing.initialize(~w[ 3 5 > if 33 else 44 then ]) == 44
+      # assert RPNForthThing.initialize(~w[ 3 5 > ? 33 44 ]) == 44
     end
 
     test "and or not" do

  # Prints the literal value of the top of the stack, popping it
  def compute([ "." | remaining_input], [x | stack], dict) do
    IO.puts x
    compute(remaining_input, stack, dict)
  end


  end

  # In-place decrement
  def compute([ "1-" | remaining_input], [x | stack], dict) do
    compute(remaining_input, [(x - 1) | stack], dict)
  end

  # In-place increment
  def compute([ "1+" | remaining_input], [x | stack], dict) do
    compute(remaining_input, [(x + 1) | stack], dict)
  end

