How does the single equal sign work in the if statement in javascript

Question

Recently I saw a statement that works in javascript on the internet and I wonder what the meaning of a single equal sign (=) in javascript as I mostly use in if statements i

Answer 1

Single "=" means "assign to the left var".

As a return value for the IF, you get the value assigned, and since it is 1, the "true" branch is executed.

However, if you put "var" into the IF, it won't return the assigned value, and I think it won't even work at all.

Mistaking "=" and "==" is a common typo.