Add support for triangular products with evaluators

Eigen/src/Core/NoAlias.h

@@ -40,6 +40,8 @@ class NoAlias
     EIGEN_DEVICE_FUNC
     EIGEN_STRONG_INLINE ExpressionType& operator=(const StorageBase<OtherDerived>& other)
     {
+      // TODO either call resize here or call "call_assignment" through m_expression.lazyAssign()  ??
+      m_expression.resizeLike(other.derived());
       call_assignment(*this, other.derived(), internal::assign_op<Scalar>());
       return m_expression;
     }