bindKey (Lodash Compatibility)

Use arrow functions or the bind method

This bindKey function operates in a complex and slow manner due to dynamic method binding and placeholder handling. Using JavaScript's native bind method or arrow functions is simpler and performs better.

Instead, use the faster and more modern arrow functions or Function.prototype.bind.

Binds a method of an object, allowing it to reference methods that may be redefined later.

const bound = bindKey(object, key, ...partialArgs);

Reference

bindKey(object, key, ...partialArgs)

Use bindKey when you want to bind a method of an object while allowing the method to be changed later. Unlike regular bind, it references the latest method each time it's called.

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

const object = {
  user: 'fred',
  greet: function (greeting, punctuation) {
    return greeting + ' ' + this.user + punctuation;
  },
};

// Bind the method.
let bound = bindKey(object, 'greet', 'hi');
bound('!');
// Returns: 'hi fred!'

// Redefine the method.
object.greet = function (greeting, punctuation) {
  return greeting + 'ya ' + this.user + punctuation;
};

// The bound function calls the new method.
bound('!');
// Returns: 'hiya fred!'

You can use placeholders to reserve argument positions.

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

const object = {
  user: 'fred',
  greet: function (greeting, punctuation) {
    return greeting + ' ' + this.user + punctuation;
  },
};

// Use a placeholder.
const bound = bindKey(object, 'greet', bindKey.placeholder, '!');
bound('hi');
// Returns: 'hi fred!'

Partially applied arguments are passed first, followed by arguments provided at call time.

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

const object = {
  add: function (a, b, c) {
    return a + b + c;
  },
};

// Set the first argument in advance.
const bound = bindKey(object, 'add', 10);
bound(20, 30);
// Returns: 60 (10 + 20 + 30)

Parameters

• object (object): The object to invoke the method on.
• key (string): The key of the method to call.
• ...partialArgs (any[], optional): The arguments to be partially applied to the method. You can use bindKey.placeholder to reserve argument positions.

Returns

((...args: any[]) => any): Returns a new bound function. This function references the latest method of the object each time it's called.