"CD" == Chris Dams <Chris.Dams@mi.infn.it> writes: CD> doesn't mean anything. Therefore I propose to add code to the CD> method matrix::eval_indexed that checks whether the indices are CD> idxes (in the sense of is_exactly_a<idx>) and to throw an CD> exception if they are not. What do other developers think?
I cannot see any advantages to make GiNaC more restrictive. If some users feel that this is dangerous in their setting then they can avoid this themselves. With the present state I can use M.i.i to denote a generic diagonal element of M and M.i~i---the sum of all such elements. Certainly other users may think on other application of such a freedom. Best wishes, Vladimir -- Vladimir V. Kisil email: kisilv@maths.leeds.ac.uk -- www: http://maths.leeds.ac.uk/~kisilv/