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Alfredo Salzillo
Alfredo Salzillo

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Can you hack this? #1

#javascript #fun #challenge

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 equal the same name property of the input object implemented like this:

const nameEqualsToItself = (person) => person.name === person.name
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Can you find the input that makes nameEqualsToItself return false?

const personX = ???
console.log(nameEqualsToItself(personX)) // print `false`
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Top comments (12)

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afif profile image
Temani Afif • • Edited 
const personX={};
personX.name=NaN;
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OR simply

const personX={name:NaN};
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a. If x or y are any of NaN, +∞𝔽, or -∞𝔽, return false. ref

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akashkava profile image
Akash Kava •

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.

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alfredosalzillo profile image
Alfredo Salzillo •

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

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atulcodex profile image
🚩 Atul Prajapati 🇮🇳 •

You don't know everything 😛

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kinzmak profile image
Kins • • Edited 
const personX = { get name() { return Math.random() } };
console.log(nameEqualsToItself(personX)); //This will return false as well
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shane profile image
Shane McGowan • • Edited

This is big brain, love it

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aminnairi profile image
Amin •

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
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rkichenama profile image
Richard Kichenama • 
const personX = new Proxy({}, { get (target, attr) { return /name/i.test(attr) ? Symbol('name') : target[attr]; });
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alfredosalzillo profile image
Alfredo Salzillo •

It print true :) try it

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ironcladdev profile image
Conner Ow •

It printed false.

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