collectInto Changes a function that accepts an array into a variadic function. Given a function, return a closure that collects all inputs into an array-accepting function. const collectInto = fn => (...args) => fn(args); const Pall = collectInto(Promise.all.bind(Promise)); let p1 = Promise.resolve(1); let p2 = Promise.resolve(2); let p3 = new Promise(resolve => setTimeout(resolve, 2000, 3)); Pall(p1, p2, p3).then(console.log); // [1, 2, 3] (after about 2 seconds)