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There are two types of destructuring possible:ĭeclare the variables inside the curly braces can be omitted. It removes the need for multiple assignments to variables It is simply fast and a clean way. We can access an object property or an array value with the destruct syntax and store it in a variable. * name = 'John Smith' Not allowed as name is a constant */ Destructuringĭestructuring means breaking down the structure of an entity into its parts.

“const” declares a variable that you cannot change later once it’s assigned a value.

* re-assignment such as: name = 'John Smith' is allowed */

“let” declares a variable that can be changed at a later point in your program.

Lexical scoping means the variable you declare will only be available inside the nearest containing block.

The reason is that let and const follow something called lexical scoping, which is very important. Now, we have two new keywords for declaring variables, let and const, in addition to var. Previously in JavaScript, variables were declared using the var keyword. We will learn different ES6 features in the subsequent sections.Īlthough there are more versions of ES, such as ES7, ES8, ES9, ES6 is the most prominent release and significant one. It is highly used together with React and is widely supported in modern browsers like Chrome and Firefox. The ES6 syntax gives you more flexibility and productive ways of writing code.

It has brought exciting new features, syntax, and methods to the JavaScript language. Exporting Default Value from a ModuleĮS6 is short for ECMAScript 2015, which is a major version of the javascript release.