Issue 4954/1: Change spanner-id to be a key instead of a string

Also changes argument \= to be a key.

Backport-by: David Kastrup <dak@gnu.org>

4 files changed, 2 insertions, 6 deletions

diff --git a/scm/define-grob-properties.scm b/scm/define-grob-properties.scm
index cb9103a6fc..7ca44b6f3d 100644
--- a/scm/define-grob-properties.scm
+++ b/scm/define-grob-properties.scm
@@ -992,7 +992,7 @@ override:
 \\override MultiMeasureRest
   #'spacing-pair = #'(staff-bar . staff-bar)
 @end example")
-     (spanner-id ,string? "An identifier to distinguish concurrent spanners.")
+     (spanner-id ,key? "An identifier to distinguish concurrent spanners.")
      (springs-and-rods ,boolean? "Dummy variable for triggering
 spacing routines.")
      (stacking-dir ,ly:dir? "Stack objects in which direction?")
diff --git a/scm/define-grobs.scm b/scm/define-grobs.scm
index f525edd69a..6ca25b586e 100644
--- a/scm/define-grobs.scm
+++ b/scm/define-grobs.scm
@@ -1787,7 +1787,6 @@
         (height-limit . 2.0)
         (minimum-length . 1.5)
         (ratio . 0.333)
-        (spanner-id . "")
         (springs-and-rods . ,ly:spanner::set-spacing-rods)
         (stencil . ,ly:slur::print)
         (thickness . 1.1)
@@ -1957,7 +1956,6 @@
         (line-thickness . 0.8)
         (minimum-length . 1.5)
         (ratio . 0.25)
-        (spanner-id . "")
         (springs-and-rods . ,ly:spanner::set-spacing-rods)
         (stencil . ,ly:slur::print)
         (thickness . 1.2)
diff --git a/scm/define-music-properties.scm b/scm/define-music-properties.scm
index 4df3f93340..f8c567d1fa 100644
--- a/scm/define-music-properties.scm
+++ b/scm/define-music-properties.scm
@@ -183,7 +183,7 @@ If zero, signals a beat containing varying durations.")
 Options are @code{'text} and @code{'hairpin}.")
      (span-text ,markup? "The displayed text for dynamic text
 spanners (e.g., cresc.)")
-     (spanner-id ,string? "Identifier to distinguish concurrent spanners.")
+     (spanner-id ,key? "Identifier to distinguish concurrent spanners.")
      (start-callback ,procedure? "Function to compute the negative length
 of starting grace notes.  This property can only be defined as initializer
 in @file{scm/@/define-music-types.scm}.")
diff --git a/scm/define-music-types.scm b/scm/define-music-types.scm
index e0190eda55..348bcd0e87 100644
--- a/scm/define-music-types.scm
+++ b/scm/define-music-types.scm
@@ -438,7 +438,6 @@ goes down).")
      . ((description . "Start or end phrasing slur.
 
 Syntax: @var{note}@code{\\(} and @var{note}@code{\\)}")
-        (spanner-id . "")
         (types . (post-event span-event event phrasing-slur-event))
         ))
 
@@ -570,7 +569,6 @@ Syntax: @code{\\skip} @var{duration}")
      . ((description . "Start or end slur.
 
 Syntax: @var{note}@code{(} and @var{note}@code{)}")
-        (spanner-id . "")
         (types . (post-event span-event event slur-event))
         ))