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jessepezzillo
2,701 PointsMaybe i'm dull... what is the point of an arrow function? Still not getting it.
basic arrow syntax video
3 Answers
Steven Parker
229,783 PointsFor one thing, it provides a more compact syntax.
But there are several functional differences as compared to traditional functions as well. One that often causes trouble for folks who overlook it is that arrow functions do not define "this" like conventional ones do.
For a complete description of the differences, see the MDN documentation page.
Cemil Yener
Courses Plus Student 3,337 PointsYou have to assign this to a variable, in this case self because whenever you create a function a new this value is defined.
Arrow functions do not have a this value defined. You can write the above code in the following way.
function Person() { this.age = 0;
setInterval(() => { this.age ++; }, 1000);
} Not worrying about this in your code is less frustrating. For more reading check the MDN documentation on Arrow Functions
Cemil Yener
Courses Plus Student 3,337 PointsThe advanced technical benefit with arrow functions comes with using callbacks in object orientated programming and using this.
In this example we're increasing a person's age by 1 ever one second.
function Person() { this.age = 0;
var self = this;
setInterval(function() { self.age ++; }, 1000);
}