#DzlTaskCacheCallback is the prototype for a function to be executed to
populate an item in the cache.
This function will be executed when a fault (cache miss) occurs from
a caller requesting an item from the cache.
The callee may complete the operation asynchronously, but MUST return
either a GObject using g_task_return_pointer() or a #GError using
g_task_return_error() or g_task_return_new_error().
#DzlTaskCacheCallback is the prototype for a function to be executed to populate an item in the cache.
This function will be executed when a fault (cache miss) occurs from a caller requesting an item from the cache.
The callee may complete the operation asynchronously, but MUST return either a GObject using g_task_return_pointer() or a #GError using g_task_return_error() or g_task_return_new_error().