30-seconds-of-code/snippets/call.md

title, tags, expertise, firstSeen, lastUpdated

title	tags	expertise	firstSeen	lastUpdated
Call functions with context	function	advanced	2017-12-22T21:54:30+02:00	2021-06-13T13:50:25+03:00

Given a key and a set of arguments, call them when given a context.

• Use a closure to call key with args for the given context.

const call = (key, ...args) => context => context[key](...args);

Promise.resolve([1, 2, 3])
  .then(call('map', x => 2 * x))
  .then(console.log); // [ 2, 4, 6 ]
const map = call.bind(null, 'map');
Promise.resolve([1, 2, 3])
  .then(map(x => 2 * x))
  .then(console.log); // [ 2, 4, 6 ]