// The only permitted playbackRate is 1.

​

class SimplePlayer extends Tone.Player {

  constructor(...args){

    super(...args);

    this.playbackRate = 1;

  }

  start(...args){

    // assuming args[0] is always time

    this.startTime = args[0] | Tone.now();

    super.start(...args);

  }

  get duration(){

    return this._buffer.duration;

  }

  currentTime(){

    return Tone.now() - this.startTime;

  }

  progress(){

    if(this.state == "started"){

       return this.currentTime() / this.duration; 

    }

    else{

      return 0;

    }

  }

  // disable setting playbackRate to anything other than 1

  set playbackRate(rate) {

    if(rate != 1) throw new Error("Setting the playbackRate value to any value other than 1 is disabled in SimplePlayer. If required, use Tone.Player instead.");

  }

}

​

​