# Source code for atom.event

    # --------------------------------------------------------------------------------------
    # Copyright (c) 2013-2025, Nucleic Development Team.
    #
    # Distributed under the terms of the Modified BSD License.
    #
    # The full license is in the file LICENSE, distributed with this software.
    # --------------------------------------------------------------------------------------
    from .catom import DelAttr, GetAttr, Member, SetAttr, Validate
    from .typing_utils import extract_types

    class Event(Member):
        """A member which acts like a stateless event."""

        __slots__ = ()

        def __init__(self, kind=None):
            """Initialize an Event.

            Parameters
            ----------
            kind : type, tuple of types or Member, optional
                The type of argument which may be emitted by the event or
                a Member which will validate the argument which can be
                emitted. The default is None and indicates no validation
                will be performed.

            """
            self.set_getattr_mode(GetAttr.Event, None)
            self.set_setattr_mode(SetAttr.Event, None)
            self.set_delattr_mode(DelAttr.Event, None)
            if kind is not None:
                if isinstance(kind, Member):
                    self.set_validate_mode(Validate.Delegate, kind)
                else:
                    self.set_validate_mode(Validate.Instance, extract_types(kind))

        def set_name(self, name):
            """A reimplemented parent class method.

            This method ensures that the delegate name is also set, if a
            delegate validator is being used.

            """
            super(Event, self).set_name(name)
            _mode, kind = self.validate_mode
            if isinstance(kind, Member):
                kind.set_name(name)

        def set_index(self, index):
            """A reimplemented parent class method.

            This method ensures that the delegate index is also set, if a
            delegate validator is being used.

            """
            super(Event, self).set_index(index)
            _mode, kind = self.validate_mode
            if isinstance(kind, Member):
                kind.set_index(index)