gras: formalize the weak container api w/ docs

address issue #69, we now have a set_container call,
which is now formally part of the api.

Anyone can call set_container for custom container types.
GRAS supports shared ptr and pyobject out of the box.

1 files changed, 3 insertions, 2 deletions

diff --git a/lib/hier_block.cpp b/lib/hier_block.cpp
index d8756a4..758af0c 100644
--- a/lib/hier_block.cpp
+++ b/lib/hier_block.cpp
@@ -40,9 +40,10 @@ void HierBlock::disconnect(const Element &elem)
 
 static Apology::Wax get_ref(const Element &elem)
 {
-    if (elem.weak_self)
+    boost::shared_ptr<WeakContainer> weak_self = elem->weak_self;
+    if (weak_self)
     {
-        boost::shared_ptr<const void> shared_self = elem.weak_self->lock();
+        boost::shared_ptr<const void> shared_self = weak_self->lock();
         if (shared_self) return shared_self;
     }
     return elem;