I'm trying to solve a callback problem with js Classes. I need if any function is performed to return data.

    class MoveSection {
  constructor(name){
    this.name = name;
    //Some code
  }
  
  nextMove{
    //Some Code
     onLeave:function(args, callback){
                console.log(args);
                if(typeof callback == "function")
                callback();
      }
    //Somecode
  }
  prevMove{
    //Some Code
     onLeave:function(args, callback){
                console.log(args);
                if(typeof callback == "function")
                callback();
     }
    //Somecode
  }
}


const section = new MoveSection("My Name");

section.onLeave(){
  console.log("Section moving in:" this.name);
}

This is dont work? How create this callback in 2 function OnMove