new special return type for the 'box' block

2 files changed, 13 insertions, 9 deletions

diff --git a/TurtleArt/tabasics.py b/TurtleArt/tabasics.py
index fe2bfa1..2943100 100644
--- a/TurtleArt/tabasics.py
+++ b/TurtleArt/tabasics.py
@@ -108,8 +108,9 @@ from talogo import (primitive_dictionary, logoerror)
 from tautils import (convert, chr_to_ord, round_int)
 from taconstants import (Color, CONSTANTS)
 from taprimitive import (ArgSlot, ConstantArg, or_, Primitive)
-from tatype import (TYPE_BOOL, TYPE_CHAR, TYPE_COLOR, TYPE_FLOAT, TYPE_INT,
-                    TYPE_NUMBER, TYPE_NUMERIC_STRING, TYPE_OBJECT, TYPE_STRING)
+from tatype import (TYPE_BOOL, TYPE_BOX, TYPE_CHAR, TYPE_COLOR, TYPE_FLOAT,
+                    TYPE_INT, TYPE_NUMBER, TYPE_NUMERIC_STRING, TYPE_OBJECT,
+                    TYPE_STRING)
 from taturtle import Turtle
 
 
@@ -1023,7 +1024,7 @@ buttons'))
                           help_string=_('Variable 1 (numeric value)'),
                           value_block=True)
         self.tw.lc.def_prim('box1', 0,
-            Primitive(self.tw.lc.prim_get_box,
+            Primitive(self.tw.lc.prim_get_box, return_type=TYPE_BOX,
                 arg_descs=[ConstantArg('box1')]))
 
         palette.add_block('box2',
@@ -1035,7 +1036,7 @@ buttons'))
                           help_string=_('Variable 2 (numeric value)'),
                           value_block=True)
         self.tw.lc.def_prim('box2', 0,
-            Primitive(self.tw.lc.prim_get_box,
+            Primitive(self.tw.lc.prim_get_box, return_type=TYPE_BOX,
                 arg_descs=[ConstantArg('box2')]))
 
         primitive_dictionary['setbox'] = Primitive(self.tw.lc.prim_set_box,
@@ -1052,8 +1053,7 @@ variable'))
         self.tw.lc.def_prim('storeinbox', 2, primitive_dictionary['setbox'])
 
         primitive_dictionary['box'] = Primitive(self.tw.lc.prim_get_box,
-            return_type=or_(TYPE_OBJECT, TYPE_STRING, TYPE_NUMBER, TYPE_FLOAT,
-                TYPE_INT, TYPE_NUMERIC_STRING, TYPE_CHAR, TYPE_COLOR),
+            return_type=TYPE_BOX,
             arg_descs=[ArgSlot(TYPE_STRING)])
         palette.add_block('box',
                           style='number-style-1strarg',
diff --git a/TurtleArt/tatype.py b/TurtleArt/tatype.py
index cf7bb03..346eb23 100644
--- a/TurtleArt/tatype.py
+++ b/TurtleArt/tatype.py
@@ -63,6 +63,7 @@ class TypeDisjunction(tuple,Type):
 
 TYPE_OBJECT = Type('object', 0)
 TYPE_BOOL = Type('bool', 5)
+TYPE_BOX = Type('box', 8)  # special type for the unknown content of a box
 TYPE_CHAR = Type('char', 1)
 TYPE_COLOR = Type('color', 2)
 TYPE_FLOAT = Type('float', 3)
@@ -115,9 +116,7 @@ def get_type(x):
             return (get_type(value)[0], True)
     elif isinstance(x, ast.Subscript):
         if x.value == BOX_AST:
-            return (TypeDisjunction((TYPE_OBJECT, TYPE_STRING, TYPE_NUMBER,
-                TYPE_FLOAT, TYPE_INT, TYPE_NUMERIC_STRING, TYPE_CHAR,
-                TYPE_COLOR)), True)
+            return (TYPE_BOX, True)
     elif isinstance(x, ast.Call):
         if isinstance(x.func, ast.Name):
             if x.func.id == 'float':
@@ -172,6 +171,11 @@ TYPE_CONVERTERS = {
     # The relation describing the type hierarchy must be transitive, i.e.
     # converting A -> C must yield the same result as converting A -> B -> C.
     # TYPE_OBJECT is the supertype of everything.
+    TYPE_BOX: {
+        TYPE_FLOAT: float,
+        TYPE_INT: int,
+        TYPE_NUMBER: float,
+        TYPE_STRING: str},
     TYPE_CHAR: {
         TYPE_INT: ord,
         TYPE_STRING: identity},