A reader that follows logs as they come (contract/streaming.md,
"Following a log"): a page, another process. Give it each event with
follow_event(); it says what the event was: "kept" (the next one),
"duplicate" or "stale" (dropped), "rewind" (a later writer went on
from an event it holds), "loss" (events were lost: read again with
follow_recover()), "malformed", or "unknown-format" (it stops).
follow_state() is what it shows of a tree.
Usage
follower(form = c("kept", "live"))
follow_event(f, event, from = NULL)
follow_state(f, tree)
follow_recover(f, tree, source, from = "store")Arguments
- form
"kept"(the kept form, or a view made from it: the same from every source) or"live"(a form that may show values the kept form lacks: only the process that gave them can give them again).- f
A follower.
- event
An event (or its JSON form).
- from
The process that gave it (a writer number), or
"store".- tree
A tree's id (its outermost call's).
- source
What gives the events again: a store, or a list of events.