JavaScript: Change function that accepts an array into a variadic function

JavaScript fundamental (ES6 Syntax): Exercise-43 with Solution

Change Function to Variadic

Write a JavaScript program to change a function that accepts an array into a variadic function.

Note: Given a function, return a closure that collects all inputs into an array-accepting function.

• Given a function, return a closure that collects all inputs into an array-accepting function.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2
// Define a function 'collectInto' that takes a function 'fn' as input and returns another function.
const collectInto = fn => 
  // The returned function takes any number of arguments 'args'.
  (...args) => 
    // Call the original function 'fn' with 'args' collected into an array.
    fn(args);

// Define a new function 'Pall' using 'collectInto' that collects all promises into a single promise.
const Pall = collectInto(Promise.all.bind(Promise));

// Create three promises 'p1', 'p2', and 'p3'.
let p1 = Promise.resolve(1);
let p2 = Promise.resolve(2);
let p3 = new Promise(resolve => setTimeout(resolve, 2000, 3));

// Call 'Pall' with the promises 'p1', 'p2', and 'p3' and log the result.
Pall(p1, p2, p3).then(console.log); // Output: [1, 2, 3] (after about 2 seconds)

Output:

[1,2,3]

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-43 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that converts a function expecting an array into a variadic function using the spread operator.
• Write a JavaScript function that wraps an existing function to allow it to accept multiple arguments instead of a single array.
• Write a JavaScript program that transforms a fixed-argument function into a variadic one while preserving its behavior.

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