treat float.__neg__ (minus sign) as a unary operator taking any argument

1 files changed, 2 insertions, 4 deletions

diff --git a/TurtleArt/taprimitive.py b/TurtleArt/taprimitive.py
index 3fe4696..7f32e34 100644
--- a/TurtleArt/taprimitive.py
+++ b/TurtleArt/taprimitive.py
@@ -290,10 +290,8 @@ class Primitive(object):
 
         # negative numbers
         elif self == float.__neg__:
-            if (len(new_arg_asts) == 1 and not new_kwarg_asts and
-                    isinstance(new_arg_asts[0], (ast.Num))):
-                pos_value = new_arg_asts[0].n
-                return ast.Num(n=-pos_value)
+            if (len(new_arg_asts) == 1 and not new_kwarg_asts):
+                return ast.UnaryOp(op=ast.USub, operand=new_arg_asts[0])
             else:
                 raise ValueError("minus sign (float.__neg__) got unexpected"
                                  " arguments: " + repr(new_arg_asts) +