Why Doesn't `bind()` Work with Arrow Functions in JavaScript?

Arrow Function Binding: An Explanation

When using arrow functions in JavaScript, developers may encounter unexpected behavior regarding the binding of 'this'. Unlike regular functions, arrow functions maintain a lexical scope, meaning they inherit the 'this' binding of the environment in which they were defined. Therefore, it is not possible to rebind 'this' within an arrow function.

Consider this example:

var f = () => console.log(this);
var o = {'a': 42};
var fBound = f.bind(o);
fBound();

In this code snippet, we attempt to bind the arrow function 'f' to the object 'o' using the '.bind()' method. However, when we call 'fBound', it outputs the global 'window' object instead of 'o'.

This is because arrow functions inherit their 'this' binding from the lexically enclosing environment, which in this case is the global execution context. As a result, 'f()' and 'fBound()' always refer to the global 'this'.

To avoid this issue, it is recommended to use regular functions when binding is required. These functions create a new execution context, allowing you to explicitly set the 'this' binding using the '.bind()' method.

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