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Can you hack this? #1

Alfredo Salzillo on March 10, 2021

Say that we have a function called nameEqualsToItself how accept a person object as input that checks if the name property of the input object equa...

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Temani Afif • Mar 10 '21 • Edited

const personX={};
personX.name=NaN;

OR simply

const personX={name:NaN};

a. If x or y are any of NaN, +∞𝔽, or -∞𝔽, return false. ^ref

Akash Kava • Mar 11 '21

It will return false only for NaN, because Number.POSITIVE_INFINITY === Number.POSITIVE_INFINITY returns true, and it is same for negative infinity as well.

Alfredo Salzillo • Mar 11 '21

Also if using a Getter or a Proxy returning different values each time :)

🚩 Atul Prajapati 🇮🇳 • Apr 11 '21

You don't know everything 😛

Kins • Mar 11 '21 • Edited

const personX = { get name() { return Math.random() } };
console.log(nameEqualsToItself(personX)); //This will return false as well

Shane McGowan • Mar 11 '21 • Edited

This is big brain, love it

Amin • Mar 12 '21

Using a Proxy.

"use strict";

const personNameEqualsItself = person => person.name === person.name;

const person = (() => {
  let boolean = true;

  return new Proxy({}, {get: (target, property) => property === "name" ? boolean = !boolean : undefined});
})();

console.log(personNameEqualsItself(person)); // false
console.log(personNameEqualsItself(person)); // false
console.log(personNameEqualsItself(person)); // false

Richard Kichenama • Apr 25 '21

const personX = new Proxy({}, { get (target, attr) { return /name/i.test(attr) ? Symbol('name') : target[attr]; });

Comment deleted

Alfredo Salzillo • Mar 10 '21

It print true :) try it

Conner Ow • Mar 11 '21

It printed false.

const nameEqualsToItself = (person) => person.name === person.name
const personX = { name: NaN, };
console.log(nameEqualsToItself(personX))