X-Git-Url: https://git.donarmstrong.com/lilypond.git?a=blobdiff_plain;f=scm%2Foutput-lib.scm;h=0921cdd36f00b20d54442206d3a063ed2e9d0d05;hb=6bf01501b96283a3218fed9277aa5b4da8f72be9;hp=c56fbc46d4f0a0790b4e42e828f6457ddf734854;hpb=3a7c967205c02b195a75074492d5fdd7b2ed4310;p=lilypond.git

diff --git a/scm/output-lib.scm b/scm/output-lib.scm
index c56fbc46d4..0921cdd36f 100644
--- a/scm/output-lib.scm
+++ b/scm/output-lib.scm
@@ -999,8 +999,8 @@ underlying accumulation.
 If @var{data} is @code{#f} or @code{'()}, it is not included in the sum."
   (cond ((or (not data) (null? data))
          func)
-        ((or (ly:unpure-pure-container func)
-             (ly:unpure-pure-container data))
+        ((or (ly:unpure-pure-container? func)
+             (ly:unpure-pure-container? data))
          (ly:make-unpure-pure-container
           (lambda rest
             (plus (apply ly:unpure-call func rest)