From: David Kastrup <dak@gnu.org>
Date: Mon, 8 Oct 2012 17:43:35 +0000 (+0200)
Subject: Add symbol-list-or-music? predicate
X-Git-Tag: release/2.17.6-1~28
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=c11f496ac9e637cf9a6c6794c631b148560548fa;p=lilypond.git

Add symbol-list-or-music? predicate

This is of interest for commands like \hide which accept either music
(to see an override) or a grob specification like Accidental or
Voice.Accidental.
---

diff --git a/scm/c++.scm b/scm/c++.scm
index d627481e5c..12c38a397f 100644
--- a/scm/c++.scm
+++ b/scm/c++.scm
@@ -51,6 +51,11 @@
 (define-public (symbol-list? x)
   (and (list? x) (every symbol? x)))
 
+(define-public (symbol-list-or-music? x)
+  (if (list? x)
+      (every symbol? x)
+      (ly:music? x)))
+
 (define-public (string-or-symbol? x)
   (or (string? x) (symbol? x)))
 
diff --git a/scm/lily.scm b/scm/lily.scm
index c8e4de05f4..1cc2a438ea 100644
--- a/scm/lily.scm
+++ b/scm/lily.scm
@@ -585,6 +585,7 @@ messages into errors.")
     (,string-or-music? . "string or music")
     (,string-or-symbol? . "string or symbol")
     (,symbol-list? . "symbol list")
+    (,symbol-list-or-music? . "symbol list or music")
     (,void? . "void")
     ))