Another way to print a matrix in Maxima

I've found Maxima's provided method for printing a matrix as TeX to produce code that isn't usable in LaTeX without a good amount of work. There are apparently conflicts with the more recent version of amsmath. Here're the beginnings of a replacement

printMatrix(a) := block([as],
     as : matrixmap(lambda([x],
                      printf(false, "~a", x)), a),
     simplode(maplist(lambda([row],
                             simplode(row, " & ")),
                                         as),
              sconc(" ", "\\\\", newline)))$

Naturally, again I have to wonder very strongly if there isn't already a better way to do this.

Looking back at diag_matrix, I'm a little embarrassed to see it is in the manual. I could've sworn I looked at all the matches for "diagonal" in the manual.