Compare Array in Javascript

JavaScript
1

I saw this piece of code in Javascript and I can’t understand why it’s false if they have exactly the same values ​​in the two variables.
Why isn’t it true instead?

 const a = [1, 2, 3]; 
 const b = [1, 2, 3]; 
 console.log(a === b) // false
2

Arrays are objects. When using === to compare objects, it will return true if and only if both sides of === are the same object.

Those are two different arrays (objects) that just happen to have identical elements.

This will print true:

const a = [1, 2, 3];
const b = a;
console.log(a === b); // true
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4

@camcode, the easiest way to think about it, when you write const a = [1, 2, 3]; what really happens is this: const a = new Array(1, 2, 3), so as new keyword suggests, every time you use literal notation you create something new - not the same.

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5

OP’s question isn’t unique to JavaScript. The comic isn’t even relevant here, since there’s no coercion involved.

6

Thanks everyone !!! Now I understand that the comparison is on object not on object’s values.
Are there other examples on compare array like that?

7

Then what would you suggest to be in the shirt instead of “JS”?

It is indeed not unique to JS, but it’s still true/relevant when understanding Javascript.

8

AFAIK only JS does that, so the JS shirt stays. Maybe PHP? Sorry I don’t really know.

Overall, I agree that it’s relevant when understanding JS. It’s just not the case given the context of the thread.