30-seconds-of-code/js/s/call-or-return.md

title, type, language, tags, author, cover, dateModified

title	type	language	tags	author	cover	dateModified
Call or return	snippet	javascript	function	chalarangelo	cows	2022-04-04T05:00:00-04:00

Calls the argument if it's a function, otherwise returns it.

• Use the typeof operator to check if the given argument is a function.
• If it is, use the spread operator (...) to call it with the rest of the given arguments. Otherwise, return it.

const callOrReturn = (fn, ...args) =>
  typeof fn === 'function' ? fn(...args) : fn;

callOrReturn(x => x + 1, 1); // 2
callOrReturn(1, 1); // 1