I have a Musixtex feature request: I would like to have a Musixtex
equivalent of TeX's \discretionary command. That is, a line break is
possible at
\mudiscretionary{<pre-break>}{<post-break>}{<no break>}
If no line break does actually occur, then <no break> is typeset; if a
line break does occur, then <pre-break> is typeset before the line break
and <post-break> is typeset after.
For example, you could then type
\mudiscretionary{\rightrepeat}{\leftrepeat}{\leftrightrepeat}
It would also be possible to automatically post a signature change twice
if it happens at a line break.
Any implementation of \mudiscretionary unfortunately requires a
modification of musixflx: In the first pass, \mudiscretionary must
record the widths of each of its three arguments in the .mx1 file. Then
musixflx must use this information to decide on line breaks. In the
second pass, \mudiscretionary must simply do as told by the .mx2 file.
In implementing \mudiscretionary, one would also have to decide what
exactly should be the meaning of "before" and "after" the line break.
Regards,
Mogens Lemvig Hansen
http://users.uniserve.com/~mlhansen
