30-seconds-of-code/snippets/bind-key.md

title, tags, cover, firstSeen, lastUpdated

title	tags	cover	firstSeen	lastUpdated
Bind object method	function,object	oven-paddle	2018-01-24T14:22:43+02:00	2020-10-18T23:04:45+03:00

Creates a function that invokes the method at a given key of an object, optionally prepending any additional supplied parameters to the arguments.

• Return a function that uses Function.prototype.apply() to bind context[fn] to context.
• Use the spread operator (...) to prepend any additional supplied parameters to the arguments.

const bindKey = (context, fn, ...boundArgs) => (...args) =>
  context[fn].apply(context, [...boundArgs, ...args]);

const freddy = {
  user: 'fred',
  greet: function(greeting, punctuation) {
    return greeting + ' ' + this.user + punctuation;
  }
};
const freddyBound = bindKey(freddy, 'greet');
console.log(freddyBound('hi', '!')); // 'hi fred!'