//! Marker types for simulation model methods.
/// Marker type for regular simulation model methods that take a mutable
/// reference to the model, without any other argument.
/// Marker type for regular simulation model methods that take a mutable
/// reference to the model and a message, without scheduler argument.
/// Marker type for regular simulation model methods that take a mutable
/// reference to the model, a message and an explicit scheduler argument.
/// Marker type for asynchronous simulation model methods that take a mutable
/// reference to the model, without any other argument.
/// Marker type for asynchronous simulation model methods that take a mutable
/// reference to the model and a message, without scheduler argument.
/// Marker type for asynchronous simulation model methods that take a mutable
/// reference to the model, a message and an explicit scheduler argument.