bpo-34750: [Enum] add `_EnumDict.update()` support (GH-23725)
This allows easier Enum construction in unusual cases, such as including dynamic member definitions into a class definition:
# created dynamically
foo_defines = {'FOO_CAT': 'aloof', 'BAR_DOG': 'friendly', 'FOO_HORSE': 'big'}
class Foo(Enum):
vars().update({
k: v
for k, v in foo_defines.items()
if k.startswith('FOO_')
})
def upper(self):
# example method
return self.value.upper()diff --git a/Lib/enum.py b/Lib/enum.py
index ed0c9ce..0070ebe 100644
--- a/Lib/enum.py
+++ b/Lib/enum.py
@@ -136,7 +136,7 @@ def __setitem__(self, key, value):
key = '_order_'
elif key in self._member_names:
# descriptor overwriting an enum?
- raise TypeError('Attempted to reuse key: %r' % key)
+ raise TypeError('%r already defined as: %r' % (key, self[key]))
elif key in self._ignore:
pass
elif not _is_descriptor(value):
@@ -157,6 +157,16 @@ def __setitem__(self, key, value):
self._last_values.append(value)
super().__setitem__(key, value)
+ def update(self, members, **more_members):
+ try:
+ for name in members.keys():
+ self[name] = members[name]
+ except AttributeError:
+ for name, value in members:
+ self[name] = value
+ for name, value in more_members.items():
+ self[name] = value
+
# Dummy value for Enum as EnumMeta explicitly checks for it, but of course
# until EnumMeta finishes running the first time the Enum class doesn't exist.