pub fn mul_matrix<M, N>(m: M, n: N) -> M::Concrete where
M: ScalarArrayVal + HasConcreteScalarArray<<<M as ScalarArray>::Scalar as Mul<N::Scalar>>::Output, N::Row, <M as ScalarArray>::Dim>,
M::Row: TwoDim<N::Scalar, N::Row> + Dim<<N::Row as Array<M::Scalar>>::Type>,
M::Dim: TwoDim<<M::Scalar as Mul<N::Scalar>>::Output, N::Row> + Array<<N::Dim as Array<<N::Row as Array<N::Scalar>>::Type>>::Type>,
N: ScalarArrayVal<Dim = <M as ScalarArray>::Row>,
N::Row: Array<M::Scalar> + Dim<<M::Scalar as Mul<N::Scalar>>::Output>,
M::Scalar: Mul<N::Scalar> + Clone,
<N::Dim as Array<<N::Row as Array<N::Scalar>>::Type>>::Type: Clone,
<M::Scalar as Mul<N::Scalar>>::Output: Add<Output = <M::Scalar as Mul<N::Scalar>>::Output>,
<M as HasConcreteScalarArray<<<M as ScalarArray>::Scalar as Mul<N::Scalar>>::Output, N::Row, <M as ScalarArray>::Dim>>::Concrete: ConcreteScalarArray,
<M::Row as HasSmaller>::Smaller: Array<M::Scalar> + Array<<N::Row as Array<N::Scalar>>::Type> + Array<<N::Row as Array<M::Scalar>>::Type>,
<M::Dim as HasSmaller>::Smaller: Array<<M::Row as Array<M::Scalar>>::Type> + Array<<N::Row as Array<<M::Scalar as Mul<N::Scalar>>::Output>>::Type>,
<N::Row as HasSmaller>::Smaller: Array<N::Scalar> + Array<<M::Scalar as Mul<N::Scalar>>::Output>,