message: improved operator[] masking for scalar 'bool' masks
diff: @@ -188,7 +188,7 @@ struct StaticArrayBase : ArrayBase<Value_, Derived_> {
  }
  using Base::operator[];
  - template <typename Mask, std::enable_if_t<Mask::Derived::IsMask, int> = 0>
  + template <typename Mask, enable_if_mask_t<Mask> = 0>
  ENOKI_INLINE auto operator[](const Mask &m) {
  return detail::MaskedArray<Derived>{ derived(), mask_t<Derived>(m) };
  }
  