Re: Make a PostEvents container class for packaging several postevents (issue 7742044)

[dak]

Reviewers: lemzwerg,

Message:
On 2013/03/16 19:19:57, lemzwerg wrote:
> LGTM.  The combination `\' `\n' `\(' is probably worth a comment in
the
> contributors' manual.

If \( was defined, things would be so much easier: one would just put \(
in the first column. \ <newline> \n( is the best I could manage.  Or
reformat in order to get the ( away from the starts of line.

Total nuisance.

Description:
Make a PostEvents container class for packaging several postevents

Previously it was not possible to assign multiple postevents to a
single variable or pass them as the result of an event function.  This
patch wraps multiple events in such situations inside of a PostEvents
post-event and unwraps them when used again in the parser.

Defuse some open parens starting lines in strings in
define-music-types.scm

Those confuse Emacs' heuristics and make it harder to edit subsequent
Scheme.

Please review this at https://codereview.appspot.com/7742044/

Affected files:
  M lily/parser.yy
  M scm/define-music-types.scm


Index: lily/parser.yy
diff --git a/lily/parser.yy b/lily/parser.yy
index  
478d05377540e10033d55fb569792645d35e3612..a02e4fc2f8b388cad3da3aeb32723e7df07c2a7b  
100644
--- a/lily/parser.yy
+++ b/lily/parser.yy
@@ -596,7 +596,26 @@ identifier_init:
        | output_def
        | context_def_spec_block
        | music_assign
-       | post_event_nofinger
+       | post_event_nofinger post_events
+       {
+               Music *m = unsmob_music ($1);
+
+               if (m->is_mus_type ("post-event-wrapper"))
+                       $$ = scm_append
+                               (scm_list_2 (m->get_property ("elements"),
+                                            scm_reverse_x ($2, SCM_EOL)));
+               else
+                       $$ = scm_cons ($1, scm_reverse_x ($2, SCM_EOL));
+               if (scm_is_pair ($$)
+                   && scm_is_null (scm_cdr ($$)))
+                       $$ = scm_car ($$);
+               else
+               {
+                       Music * m = MY_MAKE_MUSIC ("PostEvents", @$);
+                       m->set_property ("elements", $$);
+                       $$ = m->unprotect ();
+               }
+       }
        | number_expression
        | FRACTION
        | string
@@ -2490,8 +2509,20 @@ post_events:
                $$ = SCM_EOL;
        }
        | post_events post_event {
-               unsmob_music ($2)->set_spot (@2);
-               $$ = scm_cons ($2, $$);
+               Music *m = unsmob_music ($2);
+               $$ = $1;
+               if (m->is_mus_type ("post-event-wrapper"))
+               {
+                       for (SCM p = m->get_property ("elements");
+                            scm_is_pair (p);
+                            p = scm_cdr (p))
+                       {
+                               $$ = scm_cons (scm_car (p), $$);
+                       }
+               } else {
+                       m->set_spot (@2);
+                       $$ = scm_cons ($2, $$);
+               }
        }
        ;

Index: scm/define-music-types.scm
diff --git a/scm/define-music-types.scm b/scm/define-music-types.scm
index  
e7d121b411c210be1685e4b5e8362429ed7217e1..aadb447cca46fa3c27b3240590e85991334bacfc  
100644
--- a/scm/define-music-types.scm
+++ b/scm/define-music-types.scm
@@ -72,10 +72,10 @@ Syntax: @address@hidden@code{-\\arpeggio}}")
     (ArticulationEvent
      . ((description . "Add an articulation marking to a note.

-Syntax: @address@hidden@code{y}, where @code{x} is a direction
-(@code{^} for up or @code{_} for down), or LilyPond's choice
-(no direction specified), and where @code{y} is an articulation
-(such as @address@hidden, @address@hidden>}}, @code{\\tenuto}, 
@code{\\downbow}).
+Syntax: @address@hidden@code{y}, where @code{x} is a direction\
+\n(@code{^} for up or @code{_} for down), or LilyPond's choice\
+\n(no direction specified), and where @code{y} is an articulation\
+\n(such as @address@hidden, @address@hidden>}}, @code{\\tenuto},  
@code{\\downbow}).
 See the Notation Reference for details.")
        (types . (general-music post-event event articulation-event 
script-event))
        ))
@@ -437,6 +437,12 @@ Syntax: @address@hidden(} and @address@hidden)}")
        (types . (general-music post-event span-event event 
phrasing-slur-event))
        ))

+    (PostEvents
+     . ((description . "Container for several postevents.
+
+This can be used to package several events into a single one.  Should not  
be seen outside of the parser.")
+        (types . (post-event post-event-wrapper))))
+
     (PropertySet
      . ((description . "Set a context property.