template<class T>
Magnum::Math::IsScalar struct new in 2019.10

Whether T is an arithmetic scalar type.

Equivalent to std::true_type for all builtin scalar integer and floating-point types and in addition also Deg and Rad; equivalent to std::false_type otherwise. The Half type deliberately doesn't support any arithmetic, so it's not treated as a scalar type.

Note that this is different from std::is_scalar, which is true also for enums or pointers — it's rather closer to std::is_arithmetic, except that it doesn't give std::true_type for bool. The name is chosen particularly for the IsVector / IsScalar distinction.