Make user-generated tab-clefs possible

Make user-generated tab-clefs possible

Accumulates user-defined tab-clef-settings in 'clefs-settings-list' via
'make-clef-settings'.
Possible are settings for font-family, font-name and, optional, a new markup.
Makes the markup-command 'custom-tab-clef' more generic to use this list with
the modified 'clef::print-modern-tab-if-set'.
The new clefs can be used as \clef <name>
They are stored per session in 'supported-clefs' and 'c0-pitch-alist'

[thomasmorley651, 2013-09-07 22:39:16]

Remove tabs

[thomasmorley651, 2013-09-07 22:39:59]

Remove tabs

[thomasmorley651, 2013-09-07 22:45:00]

Hi,

please review.

[Ian Hulin (gmail), 2013-09-08 00:08:46]

Nit-pick re comment wording.  "is valuated by" isn't really clear, is it a
'sounds-like' error for 'evaluated' or 'validated', or the suggestion I've made
below.

Cheers,
Ian

https://codereview.appspot.com/13612043/diff/6001/scm/tablature.scm
File scm/tablature.scm (right):

https://codereview.appspot.com/13612043/diff/6001/scm/tablature.scm#newcode44
scm/tablature.scm:44: ;; The 'text'-variable is optional. If not set, it will be
valuated by
;; ... If not set, a default value will be provided in markup-command 
'custom-tab-clef', defined below.

[thomasmorley651, 2013-09-08 21:00:18]

Addressing Ian's comment

[dak, 2013-09-08 21:05:25]

https://codereview.appspot.com/13612043/diff/6001/scm/parser-clef.scm
File scm/parser-clef.scm (right):

https://codereview.appspot.com/13612043/diff/6001/scm/parser-clef.scm#newcode23
scm/parser-clef.scm:23: (define-session-public supported-clefs
Huh.  I though we had that already.

https://codereview.appspot.com/13612043/diff/6001/scm/tablature.scm
File scm/tablature.scm (right):

https://codereview.appspot.com/13612043/diff/6001/scm/tablature.scm#newcode46
scm/tablature.scm:46: (define*-public (make-clef-settings name font-family
font-name #:optional text)
Nobody will remember the order and meaning of the options.  One could use named
arguments, but since you are providing a "text" anyway, I'd make that
non-optional and leave everything else away.  As text can be a markup, it can
call upon font-family and/or font-name itself as required.

Depending on how much preformatting you want to provide, you can accept a markup
list instead of a single markup and create a center-column (or whatever else)
from it.