8ee50178f3
Correct: `Array.from()` (it’s a static method) Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method) This patch uses the common `#` syntax to denote `.prototype.`.
756 B
756 B
pipeAsyncFunctions
Performs left-to-right function composition for asynchronous functions.
Use Array.prototype.reduce() with the spread operator (...) to perform left-to-right function composition using Promise.then().
The functions can return a combination of: simple values, Promise's, or they can be defined as async ones returning through await.
All functions must be unary.
const pipeAsyncFunctions = (...fns) => arg => fns.reduce((p, f) => p.then(f), Promise.resolve(arg));
const sum = pipeAsyncFunctions(
x => x + 1,
x => new Promise(resolve => setTimeout(() => resolve(x + 2), 1000)),
x => x + 3,
async x => (await x) + 4
);
(async () => {
console.log(await sum(5)); // 15 (after one second)
})();