convert-ly behaviour with chords

[Han-Wen Nienhuys]

address@hidden writes:
> I've found some interesting behaviour with chords:
> 
> ----
> \version "1.8.1"
> \score{ \notes {
> r1
> <<a2 d>>
> }}
> ----
> address@hidden:~/tmp$ convert-ly foo.ly
> convert-ly (GNU LilyPond) 1.9.7
> Processing `tocc.ly' ... Applying conversions: 1.9.0, 1.9.1, 1.9.2, 1.9.3, 
> 1.9.4, 1.9.5, 1.9.6, 1.9.7, 
> \version "1.9.7"
> \score{ \notes {
> r1
> <<<a d>2>>
> }}
> ----
> 
> The file does compile correctly, but why is the <a d>2 chord
> enclosed in << >> ?

because

<<a2 d>>

is interpreted by convert-ly as 

< <a2 d> > 

there cannot  be a 2 within << >>

> Is this a deliberate decision?  I'm just wondering if it might be the result
> of a harmless bug (which might not be harmless in all circumstances)

I've added a rule which fixes the result for

<<a d>>2


-- 

Han-Wen Nienhuys   |   address@hidden   |   http://www.xs4all.nl/~hanwen