Function outbox_count_binding 

pub fn outbox_count_binding() -> &'static str

The page’s OUTBOX: the element events turns have asked for and not yet had delivered — how many (outbox_count_binding) and, at positions 1..=count, three parallel Int-keyed maps of selector, event and carried value — appended where the asking statement RUNS and emptied by the flush that follows a turn’s write-back.