Folds func over the elements of iter. That is to say, func will be called
as func (object, ret, user_data) for each object in it. The normal use
of this procedure is to accumulate the results of operating on the objects in
ret.
The fold will proceed as long as func returns TRUE. When the iterator has no
more arguments, GST_ITERATOR_DONE will be returned. If func returns FALSE,
the fold will stop, and GST_ITERATOR_OK will be returned. Errors or resyncs
will cause fold to return GST_ITERATOR_ERROR or GST_ITERATOR_RESYNC as
appropriate.
Folds func over the elements of iter. That is to say, func will be called as func (object, ret, user_data) for each object in it. The normal use of this procedure is to accumulate the results of operating on the objects in ret.
This procedure can be used (and is used internally) to implement the Iterator.foreach and Iterator.findCustom operations.
The fold will proceed as long as func returns TRUE. When the iterator has no more arguments, GST_ITERATOR_DONE will be returned. If func returns FALSE, the fold will stop, and GST_ITERATOR_OK will be returned. Errors or resyncs will cause fold to return GST_ITERATOR_ERROR or GST_ITERATOR_RESYNC as appropriate.
The iterator will not be freed.