Class property

Lib/enum.py:175–229

This is a descriptor, used to define attributes that act differently when accessed through an enum member and through an enum class. Instance access is the same as property(), but access to an attribute through the enum class will instead look in the class' _member_map_ for a co

        return "auto(%r)" % self.value

class property(DynamicClassAttribute):
    """
    This is a descriptor, used to define attributes that act differently
    when accessed through an enum member and through an enum class.
    Instance access is the same as property(), but access to an attribute
    through the enum class will instead look in the class' _member_map_ for
    a corresponding enum member.
    """

    member = None
    _attr_type = None
    _cls_type = None

    def __get__(self, instance, ownerclass=None):
        if instance is None:
            if self.member is not None:
                return self.member
            else:
                raise AttributeError(
                        '%r has no attribute %r' % (ownerclass, self.name)
                        )
        if self.fget is not None:
            # use previous enum.property
            return self.fget(instance)
        elif self._attr_type == 'attr':
            # look up previous attribute
            return getattr(self._cls_type, self.name)
        elif self._attr_type == 'desc':
            # use previous descriptor
            return getattr(instance._value_, self.name)
        # look for a member by this name.
        try:
            return ownerclass._member_map_[self.name]
        except KeyError:
            raise AttributeError(
                    '%r has no attribute %r' % (ownerclass, self.name)
                    ) from None

    def __set__(self, instance, value):
        if self.fset is not None:
            return self.fset(instance, value)
        raise AttributeError(
                "<enum %r> cannot set attribute %r" % (self.clsname, self.name)
                )

    def __delete__(self, instance):
        if self.fdel is not None:
            return self.fdel(instance)
        raise AttributeError(
                "<enum %r> cannot delete attribute %r" % (self.clsname, self.name)
                )

    def __set_name__(self, ownerclass, name):
        self.name = name
        self.clsname = ownerclass.__name__


class _proto_member: