A simple asyncPipe utility without any dependency to handle functions or promises

asyncPipe.js

// Quick asyncPipe utility without any dependency

const asyncPipe = (f1, ...fns) => {
  const toPromise = (fn, ...args) =>
    new Promise((resolve, reject) => {
      try {
        return resolve(fn(...args));
      } catch (e) {
        return reject(e);
      }
    });

  const isPromise = p => typeof p.then === "function";

  return (...args) =>
    fns.reduce(
      (res, fn) => res.then(fn),
      (isPromise(f1) ? f1 : toPromise(f1, ...args)).then(() => f1(...args))
    );
};

const add = a => parseInt(a, 10) + 1;
const asyncAdd = a =>
  new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve(parseInt(a, 10) + 1);
    }, 500);
  });

asyncPipe(
  add,
  asyncAdd,
  asyncAdd
)(1).then(tot => console.log("4:", tot));

// EXAMPLES

asyncPipe(
  add,
  asyncAdd,
  add
)(1).then(tot => console.log("4:", tot));

asyncPipe(
  add
)(5).then(tot => console.log("6:", tot));

asyncPipe(
 asyncAdd
)(10).then(tot => console.log("11:", tot));