Make.BranchSourceManipulate branches.
Manipulate relations between branches and commits.
find r b is Some c iff c is bound to b in t. It is None if b is not present in t.
get t b is similar to find but raise Invalid_argument if b is not present in t.
val watch :
repo ->
branch ->
?init:commit ->
(commit Irmin.Diff.t -> unit Lwt.t) ->
watch Lwt.twatch t b f calls f on every change in b.