Re: Getting pitch out of a pair

[Jay Anderson]

On Fri, Jan 16, 2015 at 4:02 PM, address@hidden <address@hidden> wrote:
> I store two pitches in a pair variable
> x = #'(b . cis')
>
> But then I want to retrieve each one as a  pitch in a music-function
> foo = #(define-music-function (parser location bar) (ly:music?)
>         (define from (car x))
>         (define to (cdr x))
>         #{
>                 \transpose $from $to $bar
>         #}
>
> but when I use this
> \foo a
>
> I get Expecting pitch, found (quote b)
>
> So what am I doing wrong and how can I do it right?
>
> // Anders
> PS! The foo function is just a snippet the real function does a bit more...

pitches = #(cons #{ b #} #{ cis' #})
#(display (ly:pitch? (car pitches)))  => #t

Notes:
- It needs to be lilypond and not scheme which interprets the pitches.
The #{ #} do that inside a scheme expression.
- It won't work within a quoted list (e.g. #'(#{ b #} . #{ cis' #})
won't get you pitches.)

-----Jay