docs: @Pure
      @XtextOperator("+")
      @SuppressWarnings("unchecked")
      public static <M extends Matrix4d> M operator_plus(double left, M right) {
          assert right != null : AssertMessages.notNullParameter(1);
          final M result = (M) right.clone();
          result.add(left, right);
          return result;
      }