What s the difference between constexpr and const

Question

What makes constexpr and const different from one another?

Can I ever just utilise one of them? When should I utilise each and how should I make my decision?

Answer 1

Variables are protected from modification in your code using the const keyword.

Constexpr instructs the compiler that this expression yields a compile-time constant value, making it suitable for usage in contexts such as array length calculations and assigning values to const variables, among other things.

They may (and should) be used together even though they are really two separate notions.