gistfile1.js

var a = [
	{
		// Look, ma, no `this`
		foo: function foo() {
			setTimeout(foo,100);
			console.log("foo");
		}
	}	
];

var b = [
	{
		// shorthand method syntax is nice, but introduces `this` issues
		// because of lack of lexical name binding
		foo() {
			setTimeout(this.foo,100); 	// ** uglier this.foo
			console.log("foo");
		}
	}
];

gistfile2.js

var a = [
  {
    // Look, ma, no `this`
    foo: function foo(count) {
      if (count < 10) {
        setTimeout(function bar(){
          if (count % 2 === 0) {
            count++;
            setTimeout(bar,100);
          }
          else {
            foo(count+2);
          }
        },100);
      }
      else {
        console.log("foo: " + count);
      }
    }
  } 
];

var b = [
  {
    foo(count) {
      if (count < 10) {
        let bar = _ => {
          if (count % 2 === 0) {
            count++;
            setTimeout(bar,100);
          }
          else {
            this.foo(count+2);
          }
        };

        setTimeout(bar,100);
      }
      else {
        console.log("foo: " + count);
      }
    }
  }
];

http://gul.ly/dhj

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