Clean up some suspicious code. There's no guarantee a constant of integer type is a ConstantInt, so it's not safe to just cast<> these to ConstantInt. (It could be a constant expression, for example) The code is shorter this way too :).

module typeinfo7;
extern(C) int printf(char*, ...);
int func(long)
{
    return 0;
}

void main()
{
    auto ti = typeid(typeof(func));
    auto s = ti.toString;
    printf("%.*s\n", s.length, s.ptr);
    assert(s == "int()");
}