Jenom pro ukázku, varianta s .call() (funkce bude vykonána a jako this bude dosazen první argument funkce call)

function myClass()
{
   this.myMethod1 = {};
   myMethod1.call(this.myMethod1);
  
   this.myMethod2 = {};
   myMethod2.call(this.myMethod2);

   function myMethod1()
   {
      this.mySubMethod11 = mySubMethod11;
      this.mySubMethod12 = mySubMethod12;

      function mySubMethod11()
      {
      }
      
      function mySubMethod12()
      {
      }
   }

   function myMethod2()
   {
      this.mySubMethod21 = mySubMethod21;
      this.mySubMethod22 = mySubMethod22;
      
      function mySubMethod21()
      {
        console.log("test");
      }
      
      function mySubMethod22()
      {
        console.log("test2");
      }
   }
}


var myclass = {};
myClass.call(myclass);

myclass.myMethod2.mySubMethod21();