JSFiddle - React, Tailwind, and code Playground

by Alexander

Babel + JSX

console.clear();


var cfg = {
    	a: 1234,
    	b: 'abc',
    	foo: function(a) { return a + 'abc' }
	},
    def = {
        a: 1,
        b: 'a'
    },
    dest;


function extend1(obj) {
	var params = $.extend(def,  obj); // _.extend, _.assign
    return params;
}

// ----------- EI9+
function _extend(target, source) {
	var a = Object.create(target);
	Object.keys(source).map(p => {
        a[p] = source[p]; //p in a && (a[p] = source[p]);
	});
	return a;
}

function extend2(obj) {
	var params = _extend(def,  obj);
    return params;
}
//----------------------------//

// ES6, Firefox, polyfill
function extend3(obj) {
    return Object.assign(def, obj);
}


//dest = extend1(cfg);
//dest = extend2(cfg);
dest = extend3(cfg);

console.log(dest.a);
console.log(dest.b);
console.log(dest.foo(123));


















////////////////////
if (!Object.assign) {
  Object.defineProperty(Object, 'assign', {
    enumerable: false,
    configurable: true,
    writable: true,
    value: function(target, firstSource) {
      'use strict';
      if (target === undefined || target === null) {
        throw new TypeError('Cannot convert first argument to object');
      }

      var to = Object(target);
      for (var i = 1; i < arguments.length; i++) {
        var nextSource = arguments[i];
        if (nextSource === undefined || nextSource === null) {
          continue;
        }

        var keysArray = Object.keys(Object(nextSource));
        for (var nextIndex = 0, len = keysArray.length; nextIndex < len; nextIndex++) {
          var nextKey = keysArray[nextIndex];
          var desc = Object.getOwnPropertyDescriptor(nextSource, nextKey);
          if (desc !== undefined && desc.enumerable) {
            to[nextKey] = nextSource[nextKey];
          }
        }
      }
      return to;
    }
  });
}