[MEI-L] mdiv and sources

[Johannes Kepper]

Hi all,

I discovered a problem with mdiv and different sources, which we need  
to clarify rather soon. When thinking about an opera transmitted in  
several sources, it is not unlikely that the sources have different  
structures, i.e. a missing scene in one source, a different order of  
scenes etc. Differing movement titles are a quite similar problem.

For movements, turns, acts, scenes etc. MEI uses the mdiv element,  
which is direct child of body and may be nested recursively. At this  
point of the tree, there is no app element allowed, which would allow  
to define multiple divs and refer to the corresponding sources.

One possibility would be to hand over this functionality to the  
section element, which can occur directly within the music. By using  
the @type, one could say that the section is really a kind of music  
division. This would cannibalize mdiv, and would also be a kind of  
misuse of section in its current form.

Perry mentions an alternative in his description of mdiv: "Another  
possible model is <!ELEMENT mdiv (score?, parts?, sourcedesc*)>
which allows meta-data to accompany an mdiv." This solution seems not  
to be too thought out yet, but seems to be more promising in my eyes.  
Could you share some more thoughts on this?

Another idea would be to have information about the structure of a  
source (which means the sequence and nesting of mdivs) in its  
sourceDesc in the header. From there we could point down into the  
music partof the file. If a sourceDesc does not point to a given mdiv,  
this movement is not part of the source (of course we could also link  
back to the description in the header). This idea is apparently also  
not too well thought out yet, but it might be an alternative.

What do you think – how should we deal with different movement names  
and structures in multiple sources?

best,
Johannes