Re: Doc bug: beams

[Nicolas Sceaux]

Le 27 sept. 09 à 10:40, Nicolas Sceaux a écrit :

> Perhaps it would be nice to show in this section how to override the  
> default
> beaming settings globally, in a \layout block; stating that instead  
> of repeating
> in each score a beam setting override like:
>
>   \overrideBeamSettings #'Score #'(4 . 4) #'end #'(((1 . 8) . (2 2 2  
> 2)))
>
> it is possible to set this behavior for all scores using (at top  
> level):
>
>   \layout {
>     \context {
>       \Score
>       beamSettings = #(cons '(((4 . 4) end) . (((1 . 8) . (2 2 2  
> 2)))) default-beam-settings)
>     }
>   }
>
> or is it considered too advanced for this section?

Oops, actually this is poor advice, as it does not work well with beam  
setting reverts.
Maybe that:

%% at the end of scm/beam-settings.scm
#(define-public (change-beam-setting time-signature rule-type grouping- 
rule beam-settings)
    "Change a default beam setting rule. It does not modify the `beam- 
settings' argument,
but returns a modified copy."
    (let* ((new-beam-settings (list-copy beam-settings))
           (current-beam-setting (assoc (list time-signature rule- 
type) new-beam-settings)))
      (if current-beam-setting
          (set-cdr! current-beam-setting (append grouping-rule (cdr  
current-beam-setting)))
          (set! new-beam-settings (cons (cons (list time-signature  
rule-type) grouping-rule)
                                        new-beam-settings)))
      new-beam-settings))

\layout {
   \context {
     \Score
     beamSettings = #(change-beam-setting '(4 . 4) 'end '(((1 . 8) .  
(2 2 2 2))) default-beam-settings)
   }
}