Issue 5057/1: Add Protected_scm::is_bound () function

[lilypond.git] / lily / protected-scm.cc

diff --git a/lily/protected-scm.cc b/lily/protected-scm.cc
index a9fabdc4f2e6fa69803b4c2aaa2c3583039d2154..3a16254187a05b0b7880a53ec9250c47071e8aee 100644 (file)
--- a/lily/protected-scm.cc
+++ b/lily/protected-scm.cc
@@ -86,3 +86,11 @@ Protected_scm::operator SCM & ()
 
   return *SCM_CARLOC (object_);
 }
+
+bool
+Protected_scm::is_bound () const
+{
+  if (SCM_CONSP (object_))
+    return !SCM_UNBNDP (SCM_CAR (object_));
+  return !SCM_UNBNDP (object_);
+}