bind

INFO

This function is only available in es-toolkit/compat for compatibility reasons. It either has alternative native JavaScript APIs or isn’t fully optimized yet.

When imported from es-toolkit/compat, it behaves exactly like lodash and provides the same functionalities, as detailed here.

Creates a function that invokes func with the this binding of thisObj and partials prepended to the arguments it receives.

The bind.placeholder value, which defaults to a symbol, may be used as a placeholder for partially applied arguments.

Note that unlike native Function#bind, this method doesn't set the length property of bound functions.

Signature

function bind<F extends Function>(func: F, thisObj?: unknown, ...partialArgs: any[]): F;

namespace bind {
  placeholder: symbol;
}

Parameters

• func (F): The function to bind.
• thisObj (any, optional): The this binding of func.
• partialArgs (any[]): The arguments to be partially applied.

Returns

(F): Returns the new bound function.

Examples

import { bind } from 'es-toolkit/compat';

function greet(greeting, punctuation) {
  return greeting + ' ' + this.user + punctuation;
}

const object = { user: 'fred' };

let bound = bind(greet, object, 'hi');
bound('!');
// => 'hi fred!'

// Bound with placeholders.
bound = bind(greet, object, bind.placeholder, '!');
bound('hi');
// => 'hi fred!'