Gets an iterator for the elements in this bin in topologically
sorted order. This means that the elements are returned from
the most downstream elements (sinks) to the sources.
This function is used internally to perform the state changes
of the bin elements.
Each element yielded by the iterator will have its refcount increased, so
unref after use.
MT safe. Caller owns returned value.
Gets an iterator for the elements in this bin in topologically sorted order. This means that the elements are returned from the most downstream elements (sinks) to the sources. This function is used internally to perform the state changes of the bin elements. Each element yielded by the iterator will have its refcount increased, so unref after use. MT safe. Caller owns returned value.