Have you used the constexpr keyword in your projects to define compile-time constants?

Yes, the keyword constexpr in C++ is used to define constants and functions that are evaluated at compile time. This helps improve performance and safety of the code, as values are computed in advance.

Example of using constexpr to define a constant and a function:

constexpr int square(int x) {
    return x * x;
}

constexpr int value = square(5); // computed at compile time

int main() {
    int arr[value]; // array size known at compile time
    return 0;
}

Using constexpr helps avoid unnecessary computations during runtime and can be useful for optimization and ensuring data immutability.