Function.prototype Methods

There are methods of Function prototype, they allow invoking a function with explicitly bound this and applied arguments.

bind

The bind method returns a bound function. This is a new function with the same body as the original, but with its this keyword set to the provided value. Additionally, it allows you to specify a sequence of arguments, which will precede any provided when the new function is called. This method can be used for creating partially applied functions.

function showThisAndArgs(...args) {
  console.log(this, ...args);
}

const binded = showThisAndArgs.bind({}, 'a', 'b');

binded('c'); // {} a b c

call and apply

Unlike bind, these methods are used to invoke a function immediately. They both accept this value as the first argument. The difference between these methods lies in how they take arguments for the function being called. The call method receives arguments provided individually, while the apply method accepts arguments provided as an array.

function showThisAndArgs(...args) {
  console.log(this, ...args);
}

showThisAndArgs.call({}, ['a', 'b']); // {} a b
showThisAndArgs.apply({}, 'a', 'b'); // {} a b