Switch in constexpr function

Found the following statement in Wiki:

C++11 introduced the concept of a constexpr-declared function; a function which could be executed at compile time. Their return values could be consumed by operations that require constant expressions, such as an integer template argument. However, C++11 constexpr functions could only contain a single expression that is returned (as well as static_asserts and a small number of other declarations).

C++14 relaxes these restrictions. Constexpr-declared functions may now contain the following: The conditional

...

branching statements if and switch

So, Is it actually possible to have a switch in a constexpr function in c++14/c++17? And, if possible, what syntax is for that? For example, I'd like to have something like this:

enum class Terrain : std::uintmax_t {
    ROAD,
    SOIL,
    GRASS,
    MUD,
    SNOW,
};

constexpr float
getStepPrice(Terrain const& terrain)
{
    switch constexpr (terrain)
    {
        case Terrain::ROAD: return 1.0f;
        ...
    }
}

---

So, Is it actually possible to have a switch in a constexpr function in c++14/c++17?

Yes.

And, if possible, what syntax is for that?

There is absolutely nothing special about the syntax, it's just a normal switch . Like this:

constexpr int fun (int i) {
    switch(i) {
        case 0: return 7;
        default: return 5;
    }
}

int main () {
    int arr[fun(3)];
}

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