ES6 Javascript Classes - define class method to an existing function -

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• es6 - declare prototype method on class import statement 3 answers

in es5 can setting prototype existing function how go es6 classes

//// es5 function existingfn = function () {     // };  function myclass () {     // constructor stuff };  myclass.prototype.newfn = function () {     // … };  myclass.prototype.existingfn = existingfn;  //// es6 class myclass {     constructor() {}      newfn() {         // …     }      // ???????     // existingfn = existingfn     // ??????? } 

ecma-script 6 class syntax syntactic sugar on regular prototype system:

class {  }  // still possible! a.prototype.dostuff = function() {  };  var existingfn = function() {};  a.prototype.existingfn = existingfn;  var instance = new a(); instance.existingfn();