Literal Notation Extensions

There are some improvements to Literal Notation syntax.

For instance:

let width = 10; 
let length = 50; 

rectangle = {     
    "width": width,
    "length": length,
    "OutputSize": function OutputSize() {
       console.log(this.width * this.length); 
    },
    "Is It a Square": function IsItASquare() {
        console.log(this.width == this.length);
    }
};

Can now be written

let width = 10; 
let length = 50; 

let lengthField = 'length'; // Creation of a dynamic field that use square bracket `[]` for reference in the object below

rectangle = {     
    width, // width is automatically assigned - takes above value     
    [lengthField]: length, // Dynamic field name using variable. It takes both the property and value in this example
    outputSize() { // shorter syntax
       console.log(this.width * this.length); // this refers to object     
    },
    "Is It a Square"() {  possibility of string name, even accepting space inside the string
        console.log(this.width == this.length);
    }
};

PS: Short way of writing outputSize: function outputSize() {...) is: outputSize() {...)

More information may be found here: Click to read more