X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fgrob-property.cc;h=c4dce927b43f86f3265348779ede3ef846f6b1b9;hb=ab685a4504e0aef61caf91085e900e05b6aa0194;hp=59a3cd68f2a2e79cf6ad3701a84320646c1812e7;hpb=8f8b3fb62d5d0776335de899b32aada69457810a;p=lilypond.git

diff --git a/lily/grob-property.cc b/lily/grob-property.cc
index 59a3cd68f2..c4dce927b4 100644
--- a/lily/grob-property.cc
+++ b/lily/grob-property.cc
@@ -55,6 +55,7 @@ Grob::internal_set_property (SCM sym, SCM v)
     {
       if (!ly_is_procedure (v)
 	  && !is_simple_closure (v)
+	  && v != ly_symbol2scm ("calculation-in-progress") 
 	  && !type_check_assignment (sym, v, ly_symbol2scm ("backend-type?")))
 	abort ();
       check_interfaces_for_property (this, sym);
@@ -108,6 +109,7 @@ Grob::internal_get_property (SCM sym) const
 
 #ifndef NDEBUG
 #include "protected-scm.hh"
+
 Protected_scm grob_property_callback_stack = SCM_EOL;
 bool debug_property_callbacks = 0;
 #endif
@@ -191,3 +193,10 @@ Grob::is_live () const
 {
   return immutable_property_alist_ != SCM_EOL;
 }
+
+
+bool
+Grob::internal_has_interface (SCM k)
+{
+  return scm_c_memq (k, interfaces_) != SCM_BOOL_F;
+}