Adding to the points made earlier, static_assert is very useful to catch certain error or problems early by doing a compile time check itself. IT makes the code robust and avoids run time issues.

Mostly it is used to ensure the types meet certain criteria or validating any constant expression.

Here I want to point out one more example to show static_assert use with template:

template <typename T>
int someFunction(T obj)
{
    static_assert(sizeof(T) == 8, “Only 64 bits parameter supported”);
}

Or

template <typename T>
int otherFunction(T obj)
{
    static_assert(std::is_integral<T>::obj, “Only integral types “are supported”);
}