text: function A() {}
  A.prototype.prop_A = 1;
  function B() {}
  B.prototype = new A;
  B.prototype.prop_B = 2;
  function C() {}
  C.prototype = new A;
  C.prototype.prop_C = 3;
  
  (new A).prop_ //+ prop_A
  ;
  (new B).prop_ //+ prop_A, prop_B
  ;
  (new C).prop_ //+ prop_A, prop_C
  