Issue 4541 (1/2) Introduce a Grob_interface class

[lilypond.git] / lily / include / grob.hh

diff --git a/lily/include/grob.hh b/lily/include/grob.hh
index 8b2c4249ea8d91ce8781f44e46538b55308e5cb1..5ef37227662f5d6de3601dff4a42f42548dc9265 100644 (file)
--- a/lily/include/grob.hh
+++ b/lily/include/grob.hh
@@ -175,6 +175,12 @@ public:
   static SCM internal_skylines_from_element_stencils (SCM, Axis);
 };
 
+template <class T>
+inline bool has_interface(Grob *g)
+{
+  return g && g->internal_has_interface (Grob_interface<T>::interface_symbol_);
+}
+
 /* unification */
 void uniquify (vector <Grob *> &);