Issue 4495 Remove unnecessary #{ .. #} constructs

Issue 4495 Remove unnecessary #{ .. #} constructs from satb template

Either because they were never needed or because the resolution of Issue 4421 (Make music functions callable from Scheme) now permits their removal.

Note: not all such constructs have been removed, even though their removal is possible, since in these cases removal would reduce clarity.

Also tidy up conditional clauses

[dak, 2015-07-18 22:02:54]

One thing that you have to be aware of is that
#{ \music #}
is not equivalent to music but rather to
(ly:music-deep-copy music (*location*))
since it creates a copy of the music and puts the point-and-click information to
the call of the containing music function.

Now I don't really know whether you want the (*location*) here: it would likely
substitute less useful origin information when everything points to the call of
the template.  But for any music that is potentially used more than once, you
definitely want a copy.  If you don't use a copy, then any \relative or
\transpose of the music in one place will appear in all other places as well,
which usually means that you get more invocations of \relative or \transpose on
any particular appearance than you intended.

https://codereview.appspot.com/253310043/diff/1/ly/staff-tkit.ly
File ly/staff-tkit.ly (right):

https://codereview.appspot.com/253310043/diff/1/ly/staff-tkit.ly#newcode60
ly/staff-tkit.ly:60: #(if dynUp
elseif cascades are bad to read in Scheme's indentation.  Rather use cond here:

#(cond (dynUp dynamicUp)
       (dynDown dynamicDown)
       (else dynamicNeutral))

https://codereview.appspot.com/253310043/diff/1/ly/vocal-tkit.ly
File ly/vocal-tkit.ly (right):

https://codereview.appspot.com/253310043/diff/1/ly/vocal-tkit.ly#newcode41
ly/vocal-tkit.ly:41: (if v1music
This does not work.  #{ << #*unspecified* >> #} ignores the given element, but
(make-simultanous-music (list ... will not do so.

Instead do something like
(delq! #f
  (list
    (make-two-voice-staff name clef v1name v2name)
    (and v1music ...)
    (and v2music ...)))

[Trevor Daniels, 2015-07-19 18:19:55]

Incorporate David's suggestions

[Trevor Daniels, 2015-07-19 18:21:39]

Thanks David

https://codereview.appspot.com/253310043/diff/1/ly/staff-tkit.ly
File ly/staff-tkit.ly (right):

https://codereview.appspot.com/253310043/diff/1/ly/staff-tkit.ly#newcode60
ly/staff-tkit.ly:60: #(if dynUp
On 2015/07/18 22:02:54, dak wrote:
> elseif cascades are bad to read in Scheme's indentation.  Rather use cond
here:
> 
> #(cond (dynUp dynamicUp)
>        (dynDown dynamicDown)
>        (else dynamicNeutral))

Done.  Here and elsewhere.

https://codereview.appspot.com/253310043/diff/1/ly/vocal-tkit.ly
File ly/vocal-tkit.ly (right):

https://codereview.appspot.com/253310043/diff/1/ly/vocal-tkit.ly#newcode41
ly/vocal-tkit.ly:41: (if v1music
On 2015/07/18 22:02:54, dak wrote:
> This does not work.  #{ << #*unspecified* >> #} ignores the given element, but
> (make-simultanous-music (list ... will not do so.
> 
> Instead do something like
> (delq! #f
>   (list
>     (make-two-voice-staff name clef v1name v2name)
>     (and v1music ...)
>     (and v2music ...)))

Done.  Aaannd ... this fixed the doc failure notified by James/Patchy last time.
 Thanks.

[Trevor Daniels, 2015-07-24 08:32:39]

Pushed to staging as
69575bfb1cb717b07edc20215e99c5b9584f949f

Author: Trevor Daniels <t.daniels@treda.co.uk>  2015-07-19 19:15:42
Committer: Trevor Daniels <t.daniels@treda.co.uk>  2015-07-24 09:25:30

    Issue 4495 Remove unnecessary #{ .. #} constructs from satb template
    
    Either because they were never needed or because the resolution
    of Issue 4421 (Make music functions callable from Scheme) now
    permits their removal.
    
    Note: not all such constructs have been removed, even though their
    removal is possible, since in these cases removal would reduce clarity.
    
    Also tidy up conditional clauses.

Closing ...