Utils: add Ring.add_and_return_erased
This commit is contained in:
parent
f145c4b196
commit
2441ad6026
@ -30,6 +30,16 @@ let add r v =
|
||||
s.pos + 1 ;
|
||||
s.data.(s.pos mod Array.length s.data) <- v
|
||||
|
||||
let add_and_return_erased r v =
|
||||
let replaced = match !r with
|
||||
| Empty _ -> None
|
||||
| Inited s ->
|
||||
if s.pos >= Array.length s.data - 1 then
|
||||
Some (s.data.(s.pos mod Array.length s.data))
|
||||
else
|
||||
None in
|
||||
add r v ; replaced
|
||||
|
||||
let add_list r l = List.iter (add r) l
|
||||
|
||||
let last r =
|
||||
|
@ -9,12 +9,34 @@
|
||||
|
||||
(** Imperative Ring Buffer *)
|
||||
|
||||
(** An imperative ring buffer: a mutable structure that holds at most
|
||||
a fixed number of values of a same type. Values are never removed,
|
||||
once the limit is reached, adding a value replaces the oldest one
|
||||
in the ring buffer. *)
|
||||
type 'a t
|
||||
|
||||
(** Allocates a ring buffer for a given number of values. *)
|
||||
val create : int -> 'a t
|
||||
|
||||
(** Adds a value, dropping the oldest present one if full. *)
|
||||
val add : 'a t -> 'a -> unit
|
||||
|
||||
(** Same as {!add}, but returns the dropped value if any. *)
|
||||
val add_and_return_erased : 'a t -> 'a -> 'a option
|
||||
|
||||
(** Adds the values of a list, in order. *)
|
||||
val add_list : 'a t -> 'a list -> unit
|
||||
|
||||
(** Retrieves the most recent value, or [None] when empty. *)
|
||||
val last : 'a t -> 'a option
|
||||
|
||||
exception Empty
|
||||
|
||||
(** Same as {!last}, but raises {!Empty} when empty. *)
|
||||
val last_exn : 'a t -> 'a
|
||||
|
||||
(** Iterates over the elements, oldest to newest. *)
|
||||
val fold : 'a t -> init:'b -> f:('b -> 'a -> 'b) -> 'b
|
||||
|
||||
(** Retrieves the elements as a list, oldest first.. *)
|
||||
val elements : 'a t -> 'a list
|
||||
|
Loading…
Reference in New Issue
Block a user