music functions and markups

[Nicolas Sceaux]

Hello

I would like to define a music function taking a markup as an
argument.
Currently, I'm doing:

  foo = #(def-music-function (location markp music) (markup? ly:music?)
           ...)
  \foo #(markup ...)
       { c' d' e' f' }

Is there a way to be able to write, eg:

  \foo \markup { ... }
       { c' d' e' f' }

or a clue on how it could be implemented? If that is not easy,
#(markup ..) will still be fine, though less convenient than \markup.

I'm using LilyPond from CVS.

nicolas