use of set Timing.measurePosition is disrupting automatic beaming

[Roderick Mackenzie]

Hallo,

I am learning how to write bagpipe tunes with Lilypond. Bagpipe tunes
are usually in parts with a partial measure at the start and end of
each part. In order to avoid the warnings about use of "\partial"
within the body of the score I am trying to use "\set
Timing.measurePosition = #(ly:make-moment -3/8)". My problem is that
this command seems to disrupt the automatic beaming: the half measure
before the command is always printed as individual notes. In the
attached fragment the first one and a half measures are correctly
beamed but then the last half bar has no beaming. What am I doing
wrong?

Regards,
Roddy Mackenzie

fragment.ly
Description: Text Data

fragment.pdf
Description: Adobe PDF document