bpo-37062: Enum: add extended AutoNumber example (GH-22349) (GH-22370)
(cherry picked from commit 62e40d8450b9c78346ec3617de7fe3f0ad381510)
Co-authored-by: Ethan Furman <ethan@stoneleaf.us>
diff --git a/Doc/library/enum.rst b/Doc/library/enum.rst
index 5f0762e..a3c5165 100644
--- a/Doc/library/enum.rst
+++ b/Doc/library/enum.rst
@@ -887,6 +887,32 @@
>>> Color.GREEN.value
2
+To make a more general purpose ``AutoNumber``, add ``*args`` to the signature::
+
+ >>> class AutoNumber(NoValue):
+ ... def __new__(cls, *args): # this is the only change from above
+ ... value = len(cls.__members__) + 1
+ ... obj = object.__new__(cls)
+ ... obj._value_ = value
+ ... return obj
+ ...
+
+Then when you inherit from ``AutoNumber`` you can write your own ``__init__``
+to handle any extra arguments::
+
+ >>> class Swatch(AutoNumber):
+ ... def __init__(self, pantone='unknown'):
+ ... self.pantone = pantone
+ ... AUBURN = '3497'
+ ... SEA_GREEN = '1246'
+ ... BLEACHED_CORAL = () # New color, no Pantone code yet!
+ ...
+ >>> Swatch.SEA_GREEN
+ <Swatch.SEA_GREEN: 2>
+ >>> Swatch.SEA_GREEN.pantone
+ '1246'
+ >>> Swatch.BLEACHED_CORAL.pantone
+ 'unknown'
.. note::