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JavaScript

Posted by Natalie Forster
Natalie Forster
1,710 Points

So, when using a const vs a let variable, I thought const was not able to be changed or was immutable? We can add to it?

In other words, it looks here like we are able to add to the "box" of data that is held within the const variable type but cannot change or remove what is already held in it? Does that also mean that when adding new information to the message variable, that the new information then becomes immutable? Would love to understand more!

2 Answers

Natalie Forster
Natalie Forster
1,710 Points

That is definitely helpful, thank you!

Adam N
Adam N
70,280 Points

np! You can mark this question as solved by selecting a "best answer". :+1:

Adam N
Adam N
70,280 Points
Adam N
Adam N
70,280 Points

An easier way to think about it is that const prevents reassignment. So, we can't change a const variable to a different array , but we can add things to the array that's already assigned to it. Example:

const arr = [1, 2, 3]

// TypeError: Assignment to constant variable.
arr = [4, 5, 6]

// adding is all good
arr.push(7)

Let me know if this helps!