JSFiddle - React, Tailwind, and code Playground

by marcosc

JavaScript

(function(){
  "use strict";
  var name = "CustomThing";

  //makes us custom "actions" - could be anything
  function CustomAction ( id ) {
     this.x = Math.random();
     this.y = Math.random();
     var id = "This has id " + id
     //define a read only getter, for fun
     Object.defineProperty(this, "id", {get: function(){return id}})
  } 

  //implement it
  var func = new Function("name", "action",
              " return function " + name + "(id){ "+
              //only allow creation with new keyword
              " if(this === window) throw TypeError('Invalid constructor! try using new');" +
              " return Object.create(new action(id)); };"
  )(name, CustomAction);

  //Add it to the window object;
  Object.defineProperty(window, name, {value: func } )
})();

//Some Tests
try{
  CustomThing();
}catch(e){
   //TypeError: Invalid constructor! try using new
   console.log(e)
}

//Gives you a CustomAction object
var cust = new CustomThing("test");

//check the console
console.dir(cust);
console.log(cust.x);
console.log(cust.y);
console.log(cust.id);