Re: Is there an equivalent of #define ... #ifndef ... #endif in lilypond?

[David Kastrup]

Michael Hendry <address@hidden> writes:

>> Ok, tags work with music, not with books.  Here is what I would suggest:
>> 
>> ConcertBook =
>> \book {
>>   ...
>> }
>> 
>> and then you can at a later point of time say
>> 
>> \ConcertBook
>> 
>> and can comment that line out or not.  Assigning #f to ConcertBook when
>> a command line option is set is a bit trickier, but still reasonably
>> easy.
>> 
> That sounds good, but when I tried it I got...
>
> address@hidden:~/indigo/workspace/TestTag$ lilypond score.ly
> GNU LilyPond 2.14.2
> Processing `score.ly'
> Parsing...
> score.ly:92:0: error: syntax error, unexpected BOOK_IDENTIFIER
>
> \ConcertBook

Pffft.  Taking a look at the LilyPond grammar (it is also in an appendix
in the notation manual), it turns out that you have to write

\book { \ConcertBook }

here.  Turns out that a book identifier can be used in both \bookpart
and \book.  That's a bit more for outcommenting and it becomes harder to
use this conditionally.

-- 
David Kastrup