Reflect.construct() — JS Technical Interview Questions & Answers

Calls a constructor with an explicit argument array.

Reflect.construct()

  • Reflect.construct() is a JS topic. In plain words you use it for let total = 0 in a cart script. Don’t start with a slogan — start with that picture.
  • Smallest example: let for change, const for fixed. Type it, run it, and say what you see. If you can do that from memory, you know Reflect.construct().
  • From the example next to this theory: Calls a constructor with an explicit argument array.
  • Trap: var leak / const reassign. Fix that before you talk about advanced JS.
  • Viva: what is Reflect.construct()? Then show let for change, const for fixed. Then name the trap.

Technical Interview Tip: What is Reflect.construct()? Show this: let for change, const for fixed. Trap: var leak / const reassign.

Code Examples for Reflect.construct()

Reflect.construct() — working example

// Topic: Reflect.construct()
const nums = [1, 2, 3];
const doubled = nums.map((n) => n * 2);
console.log(doubled);
console.log(doubled.reduce((a, b) => a + b, 0));

Reflect.construct(): map then reduce on [1, 2, 3]. Say both prints.

How to Explain Reflect.construct() to an Interviewer

What is Reflect.construct()?

Used for let total = 0 a cart script Not just the heading

Give one small example of Reflect.construct().

let for change, const for fixed Calls a constructor with an explicit argument array

What mistake do beginners make with Reflect.construct()?

var leak / const reassign Show the fix

Where do you use Reflect.construct()?

a cart script let total = 0