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GiandoDev
GiandoDev

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Arrow function

Arrow function is a syntactic sugar which ES6 brings us.
Here an example of a simple arrow function:
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If we have just one parameter in our function we may write our arrow function in two ways:
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Maybe we don't have any parameter and we have still two options:
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Arrow function provide, by default, an implicit return statement if two condition are present:
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Top comments (5)

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nerdychap profile image
Siyabonga Hlengwa

This is a great and easy way to explain switching from the old way of defining functions to using arrow functions.

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souvikm40766885 profile image
Souvik Mandal

Why need arrow function?
Is it comes with just short our code or ........what?

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arif profile image
arif

Arrow functions do not have a arguments array

In JS arguments array in functions is a special object that can be used to get all the arguments passed to the function. Similar to this, arrow functions do not have their own binding to a arguments object, they are bound to arguments of enclosing scope.

Arrow functions are callable but not constructable

If a function is constructable, it can be called with new, i.e. new User(). If a function is callable, it can be called without new (i.e. normal function call).

Functions created through function declarations / expressions are both constructable and callable.

Arrow functions (and methods) are only callable. class constructors are only constructable.

If you are trying to call a non-callable function or to construct a non-constructable function, you will get a runtime error

let arrowFunc = () => {}
new arrowFunc()
This code gives the error:
arrowFunc is not a constructor

source

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Artem • Edited

Not really. Arrow functions don't have their own this, which can be handy in some cases.

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giandodev profile image
GiandoDev

I don’t want to sell you my point of view, instead I suggest you read what they say here and get your own idea based on your style of writing code.
developer.mozilla.org/en-US/docs/W...