Introduce void? predicate

diff --git a/scm/c++.scm b/scm/c++.scm
index 74f58f4da3f4da2449535f0faf6ca1034c85dcd0..915e7e62830c07f635abcfc647fa666c57701879 100644 (file)
--- a/scm/c++.scm
+++ b/scm/c++.scm
@@ -61,6 +61,9 @@
 (define-public (symbol-or-boolean? x)
   (or (symbol? x) (boolean? x)))
 
+(define-public (void? x)
+  (eq? x (begin)))
+
 ;; moved list to end of lily.scm: then all type-predicates are
 ;; defined.
 (define type-p-name-alist '())

diff --git a/scm/lily.scm b/scm/lily.scm
index 9157337ad1261f35e914978c5a182913e6b93f62..88f1183b926dcf19e4cabcc9cc4f373a335a1e67 100644 (file)
--- a/scm/lily.scm
+++ b/scm/lily.scm
@@ -535,6 +535,7 @@ LilyPond safe mode.  The syntax is the same as `define*-public'."
     (,scheme? . "any type")
     (,string-or-pair? . "string or pair")
     (,string-or-symbol? . "string or symbol")
+    (,void? . "void")
     ))
 
 (define-public lilypond-exported-predicates