From: David Kastrup <dak@gnu.org>
Date: Thu, 7 May 2015 19:21:54 +0000 (+0200)
Subject: Define derived_unsmob<class T> function
X-Git-Tag: release/2.19.21-1~51
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=428488bdc1a29c40b7b2326be3587270c49ff86a;p=lilypond.git

Define derived_unsmob<class T> function

This is a shortcut for dynamic_cast<T *>(T::unsmob (...)) in order to
provide an unsmob function for derived classes.
---

diff --git a/lily/include/smobs.hh b/lily/include/smobs.hh
index 2787750ec5..138bf36346 100644
--- a/lily/include/smobs.hh
+++ b/lily/include/smobs.hh
@@ -234,6 +234,14 @@ public:
   }
 };
 
+// derived_unsmob includes a dynamic_cast:
+
+template <class T>
+inline T *derived_unsmob (SCM arg)
+{
+  return dynamic_cast<T *> (T::unsmob (arg));
+}
+
 // Simple smobs
 template <class Super>
 class Simple_smob : public Smob_base<Super> {