renumbering numeric comments

[Steven Arntson]

Greetings! I'm very curious what more knowledgeable souls would do in
the following situation. I'm writing music using emacs' lilypond
mode. In Lilypond, measure numbers are usually (so far in my experience)
entered as comments at the end of a line in the form `%m__':

         \tempo 4=100
         e4 d e8 f | %m1
         \tempo 4=130
         <c a>2. | %m2
         <d e,>2 ~ <d e,>8 e | %m3
         ...
         
These "%m_" numbers are very useful in debugging when the "code" is
compiled. However, in the above case I later inserted two new measures:

         \tempo 4=100
         e4 d e8 f | %m1
         \tempo 4=130
----->   g8 f e d e f |
----->   e d c b c d |
         <c a>2. | %m2
         <d e,>2 ~ <d e,>8 e | %m3
         ...
         
Renumbering everything by hand is a lot of work, because the piece is
many measures long. I have limited technical expertise, but would love
ideas about better methods than "by hand!" Thank you!

Steven Arntson