re: Typical JavaScript interview exercises (explained) VIEW POST

FULL DISCUSSION
 

To be very thorough:

Object.freeze(heroes);
const newHeroes = heroes.map(h => {
  Object.freeze(h);
  return { ...h, name: h.name.toUpperCase() }
})
 

Why would you need to freeze it? This stuff is synchronous, how would it change in the middle of your operation?

 

It's to guard against future changes. But the requirement was to "preserve immutability" and so this makes the original data set immutable going forward.

code of conduct - report abuse