What's the Mystery Behind `{a, b, c}` in JavaScript Object Literals?

Unraveling the Mystery of {a, b, c} in JavaScript Object Literals

In the realm of JavaScript, object literals hold a prominent place. While the conventional syntax for creating objects, such as {a: a, b: b, c: c}, is well-known, the introduction of ES6 has brought about a peculiar construct: {a, b, c}. What exactly is this enigmatic notation?

To unravel its nature, let's embark on a journey into the code you provided. Consider the following line:

var f = {a, b, c};

What kind of data structure is f? Is it a mere shorthand for the verbose object literal we know so well?

The answer lies in the annals of ECMAScript 2015, where this construct emerged as Property Value Shorthands. This shorthand syntax, also known as property value shorthand, has the same effect as the conventional object literal:

var f = {a: a, b: b, c: c};

It enables you to simplify object literal creation when the property keys match the variable names, streamlining your code.

Furthermore, you can combine shorthand notation with classical initialization as seen here:

var f = {a: 1, b, c};

For a comprehensive understanding of property definitions in object initializers, delve into the depths of the Property Definitions in Object Initializer documentation.

In essence, {a, b, c} is a concise way to define an object literal where the property keys correspond to the variable names, saving you the effort of explicitly specifying each property.

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