calling eval() in particular context

Question

I have following javaScript \"class\":

A = (function() {
   a = function() { eval(...) };
   A.prototype.b = function(arg1, arg2) { /* do something... */};
}         


        

Answer 1

Folks, I think that I have the definitive answer. It works on both JavaScript (Browsers) and NodeJs.

function evalInContext(Context,toEval){
  return eval(`(function Main(){${toEval}})`).call(Context);
}

var context = {a:42,b:82,c:103};
var toEval = "return this";

console.log(evalInContext(context,toEval));//{"a": 42, "b": 82, "c": 103}

Tested on Node v12.16.1, Node v14.7.0, Firefox v79.0 and Google Chrome v84.0.4147.105