Macro handler_blueprint 

macro_rules! handler_blueprint {
    ($name:ident, Event = $event:ty, Params = $params:ty) => { ... };
}

Declares a handler Blueprint key struct.

Examples

handler_blueprint!(OnTick, Event = u32, Params = (Res<'static, u64>, ResMut<'static, bool>));

Expands to a unit struct + Blueprint impl. The 'static on Res/ResMut is required (declarative macro limitation). Future proc macros will inject it automatically.