I'd expect "hello" - 1 to return NaN, since you can't perform numerical subtraction on something that isn't a number. That's exactly what Javascript does.
In the same way, I'd expect "hello" + 1 to return Nan, since you can't perform string concatenation on something that isn't a string, and you can't perform numerical addition on something that isn't a number.
I'd expect "hello" - 1 to return NaN, since you can't perform numerical subtraction on something that isn't a number. That's exactly what Javascript does.
In the same way, I'd expect "hello" + 1 to return Nan, since you can't perform string concatenation on something that isn't a string, and you can't perform numerical addition on something that isn't a number.
Edited for clarity