Templated vec

[bearophile]

This version works, but it requires a hidden field with distinct name (and no gensym at compile time is available). Do you know a better solution that avoids the need for the distinct hidden field?


struct Vec(size_t N) {
    enum size_t _hiddenVecLength = N;
    void opBinary(string op:"~", T)(T) if (IsVec!T) {}
}
struct Fake(size_t N) {
    enum size_t _hiddenVecLength = N;
}
template IsVec(T) {
    enum bool IsVec = is(typeof(T._hiddenVecLength) == size_t)
                      /* && is(T == Vec!(T._hiddenVecLength)) */ ;
}
void main() {
    Vec!2 a1;
    Vec!3 a2;
    a1 ~ a2;
    Fake!3 f;
    a1 ~ f; // bug
}

Bye,
bearophile