(car ) was the trick I would have been looking for a long time to come up with that one.
(car (...))- returns the first member of a list.
I'm assuming that if that member is a function it returns the functions result, which is why we get the solution?
Scott
-----Original Message----- From: Michael Ellis [mailto:address@hidden Sent: Saturday, January 29, 2011 07:01 PM To: address@hidden Cc: address@hidden Subject: Re: Nesting ly:music-property error
Sorry, my previous answer was rubbish. The following runs without
error and prints the pitch object.
myN = #(define-music-function (parser location myx ) (ly:music?)
(display-scheme-music
(ly:music-property
(car (ly:music-property myx 'elements))
'pitch))
myx)
\myN c
Cheers,
Mike
On Sat, Jan 29, 2011 at 6:46 PM, Michael Ellis
wrote:
> Hi Scott,
>
> I think the problem is that the music in your example doesn't have an
> 'elements property. You can eliminate the error by changing the third
> line in your code to
>
> #(display-scheme-music (ly:music-property $myx 'pitch))
>
> but what gets displayed is an empty list '(). Probably not what you
> want, right?
>
> Some of the more experienced Schemers on the list may be able to offer
> better help.
>
> Cheers,
> Mike
>
>
>
> On Sat, Jan 29, 2011 at 6:28 PM, wrote:
>> myN = #(define-music-function (parser location myx ) (ly:music?)
>> #{
>> #(display-scheme-music (ly:music-property (ly:music-property $myx 'elements)
>> 'pitch))
>> #})
>>
>> \myN c
>