Near Procedure Call.

Usage

// Create a NPC
final npc = NPC();
npc.send = (message) async{
    // send message
};

//call when message received:
await npc.receive(message);

// register handle
npc.on('ping', (param, cancelable, notify)=>'pong');

// emit
await npc.emit('say', 'hello');

// deliver
final r = await npc.deliver('download', param: '/path', onNotify: (param){

});

Try the example for more usage.