Streamline properly maintains `this` before and after async calls... <3

animal_.js

function Animal(name) {
    this.name = name;
}

Animal.prototype.drink = function (_) {
    console.log(this.name + " is about to grab a drink at the watering hole...");

    // simulate async step:
    setTimeout(_, 1000);

    console.log(this.name + " finished drinking.");
};

var cheetah = new Animal('Bob the Cheetah');
cheetah.drink(_);