1 files changed, 31 insertions, 2 deletions
diff --git a/Doc/library/enum.rst b/Doc/library/enum.rst
index a3d5afcb9e..827bab0c90 100644
--- a/Doc/library/enum.rst
+++ b/Doc/library/enum.rst
@@ -257,7 +257,7 @@ members are not integers (but see `IntEnum`_ below)::
     >>> Color.red < Color.blue
     Traceback (most recent call last):
       File "<stdin>", line 1, in <module>
-    TypeError: unorderable types: Color() < Color()
+    TypeError: '<' not supported between instances of 'Color' and 'Color'
 
 Equality comparisons are defined though::
 
@@ -558,7 +558,8 @@ Some rules:
 4. %-style formatting:  `%s` and `%r` call the :class:`Enum` class's
    :meth:`__str__` and :meth:`__repr__` respectively; other codes (such as
    `%i` or `%h` for IntEnum) treat the enum member as its mixed-in type.
-5. :meth:`str.format` (or :func:`format`) will use the mixed-in
+5. :ref:`Formatted string literals <f-strings>`, :meth:`str.format`,
+   and :func:`format` will use the mixed-in
    type's :meth:`__format__`.  If the :class:`Enum` class's :func:`str` or
    :func:`repr` is desired, use the `!s` or `!r` format codes.
 
@@ -747,6 +748,15 @@ besides the :class:`Enum` member you looking for::
 
 .. versionchanged:: 3.5
 
+Boolean evaluation: Enum classes that are mixed with non-Enum types (such as
+:class:`int`, :class:`str`, etc.) are evaluated according to the mixed-in
+type's rules; otherwise, all members evaluate as ``True``.  To make your own
+Enum's boolean evaluation depend on the member's value add the following to
+your class::
+
+    def __bool__(self):
+        return bool(self.value)
+
 The :attr:`__members__` attribute is only available on the class.
 
 If you give your :class:`Enum` subclass extra methods, like the `Planet`_
@@ -766,3 +776,22 @@ appropriately.
 If you wish to change how :class:`Enum` members are looked up you should either
 write a helper function or a :func:`classmethod` for the :class:`Enum`
 subclass.
+
+To help keep Python 2 / Python 3 code in sync a user-specified :attr:`_order_`,
+if provided, will be checked to ensure the actual order of the enumeration
+matches::
+
+    >>> class Color(Enum):
+    ...     _order_ = 'red green blue'
+    ...     red = 1
+    ...     blue = 3
+    ...     green = 2
+    ...
+    Traceback (most recent call last):
+    ...
+    TypeError: member order does not match _order_
+
+.. note::
+
+    In Python 2 code the :attr:`_order_` attribute is necessary as definition
+    order is lost during class creation.