ClassVar must be defined before Any in Python2

gvanrossum · Sep 10, 2016 · Sep 9, 2016 · Sep 9, 2016 · Sep 9, 2016 · Sep 9, 2016
commit 69a45026d11516543bb7b5abff048b3633991f7f
diff --git a/python2/typing.py b/python2/typing.py
@@ -321,6 +321,69 @@ def _type_repr(obj):
         return repr(obj)
 
 
+class _ClassVar(object):
+    """Special type construct to mark class variables.
+
+    An annotation wrapped in ClassVar indicates that a given
+    attribute is intended to be used as a class variable and
+    should not be set on instances of that class. Usage::
+
+      class Starship:
+          stats = {}  # type: ClassVar[Dict[str, int]] # class variable
+          damage = 10 # type: int                      # instance variable
+
+    ClassVar accepts only types and cannot be further subscribed.
+
+    Note that ClassVar is not a class itself, and should not
+    be used with isinstance() or issubclass().
+    """
+
+    __metaclass__ = TypingMeta
+
+    def __init__(self, tp=None, _root=False):
+        cls = type(self)
+        if _root:
+            self.__type__ = tp
+        else:
+            raise TypeError('Cannot initialize {}'.format(cls.__name__[1:]))
+
+    def __getitem__(self, item):
+        cls = type(self)
+        if self.__type__ is None:
+            return cls(_type_check(item,
+                       '{} accepts only types.'.format(cls.__name__[1:])),
+                       _root=True)
+        raise TypeError('{} cannot be further subscripted'
+                        .format(cls.__name__[1:]))
+
+    def _eval_type(self, globalns, localns):
+        return type(self)(_eval_type(self.__type__, globalns, localns),
+                          _root=True)
+
+    def _get_type_vars(self, tvars):
+        if self.__type__:
+            _get_type_vars(self.__type__, tvars)
+
+    def __repr__(self):
+        cls = type(self)
+        if not self.__type__:
+            return '{}.{}'.format(cls.__module__, cls.__name__[1:])
+        return '{}.{}[{}]'.format(cls.__module__, cls.__name__[1:],
+                                  _type_repr(self.__type__))
+
+    def __hash__(self):
+        return hash((type(self).__name__, self.__type__))
+
+    def __eq__(self, other):
+        if not isinstance(other, _ClassVar):
+            return NotImplemented
+        if self.__type__ is not None:
+            return self.__type__ == other.__type__
+        return self is other
+
+ClassVar = _ClassVar(_root=True)
+
+
 class AnyMeta(TypingMeta):
     """Metaclass for Any."""
 
@@ -1133,69 +1196,6 @@ def __new__(cls, *args, **kwds):
             return obj
 
 
-class _ClassVar(object):
-    """Special type construct to mark class variables.
-
-    An annotation wrapped in ClassVar indicates that a given
-    attribute is intended to be used as a class variable and
-    should not be set on instances of that class. Usage::
-
-      class Starship:
-          stats = {}  # type: ClassVar[Dict[str, int]] # class variable
-          damage = 10 # type: int                      # instance variable
-
-    ClassVar accepts only types and cannot be further subscribed.
-
-    Note that ClassVar is not a class itself, and should not
-    be used with isinstance() or issubclass().
-    """
-
-    __metaclass__ = TypingMeta
-
-    def __init__(self, tp=None, _root=False):
-        cls = type(self)
-        if _root:
-            self.__type__ = tp
-        else:
-            raise TypeError('Cannot initialize {}'.format(cls.__name__[1:]))
-
-    def __getitem__(self, item):
-        cls = type(self)
-        if self.__type__ is None:
-            return cls(_type_check(item,
-                       '{} accepts only types.'.format(cls.__name__[1:])),
-                       _root=True)
-        raise TypeError('{} cannot be further subscripted'
-                        .format(cls.__name__[1:]))
-
-    def _eval_type(self, globalns, localns):
-        return type(self)(_eval_type(self.__type__, globalns, localns),
-                          _root=True)
-
-    def _get_type_vars(self, tvars):
-        if self.__type__:
-            _get_type_vars(self.__type__, tvars)
-
-    def __repr__(self):
-        cls = type(self)
-        if not self.__type__:
-            return '{}.{}'.format(cls.__module__, cls.__name__[1:])
-        return '{}.{}[{}]'.format(cls.__module__, cls.__name__[1:],
-                                  _type_repr(self.__type__))
-
-    def __hash__(self):
-        return hash((type(self).__name__, self.__type__))
-
-    def __eq__(self, other):
-        if not isinstance(other, _ClassVar):
-            return NotImplemented
-        if self.__type__ is not None:
-            return self.__type__ == other.__type__
-        return self is other
-
-ClassVar = _ClassVar(_root=True)
-
-
 def cast(typ, val):
     """Cast a value to a type.