simon/ocaml-containers
1
0
Fork 0
mirror of https://github.com/c-cube/ocaml-containers.git synced 2025-12-07 11:45:31 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

CCMultiSet.{add_mult,remove_mult,update}

Browse source
This commit is contained in:
Simon Cruanes 2014-11-23 11:54:37 +01:00
parent 4d0d988f4c
commit 13862b5133
2 changed files with 56 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

44
core/CCMultiSet.ml
View file

@ -45,6 +45,12 @@ module type S = sig
val remove : t -> elt -> t
val add_mult : t -> elt -> int -> t
val remove_mult : t -> elt -> int -> t
val update : t -> elt -> (int -> int) -> t
val min : t -> elt
val max : t -> elt
@ -102,12 +108,31 @@ module Make(O : Set.OrderedType) = struct
let n = count ms x in
M.add x (n+1) ms
let remove ms x =
let add_mult ms x n =
if n < 0 then invalid_arg "CCMultiSet.add_mult";
if n=0
then ms
else M.add x (count ms x + n) ms
let remove_mult ms x n =
if n < 0 then invalid_arg "CCMultiSet.remove_mult";
let cur_n = count ms x in
let new_n = cur_n - n in
if new_n <= 0
then M.remove x ms
else M.add x new_n ms
let remove ms x = remove_mult ms x 1
let update ms x f =
let n = count ms x in
match n with
| 0 -> ms
| 1 -> M.remove x ms
| _ -> M.add x (n-1) ms
match f n with
| 0 ->
if n=0 then ms else M.remove x ms
| n' ->
if n' < 0
then invalid_arg "CCMultiSet.udpate"
else M.add x n' ms
let min ms =
fst (M.min_binding ms)
@ -197,3 +222,12 @@ module Make(O : Set.OrderedType) = struct
seq (fun x -> m := add !m x);
!m
end
(*$T
let module S = CCMultiSet.Make(String) in \
S.count (S.add_mult S.empty "a" 5) "a" = 5
let module S = CCMultiSet.Make(String) in \
S.count (S.remove_mult (S.add_mult S.empty "a" 5) "a" 3) "a" = 2
let module S = CCMultiSet.Make(String) in \
S.count (S.remove_mult (S.add_mult S.empty "a" 4) "a" 6) "a" = 0
*)

17
core/CCMultiSet.mli
View file

@ -45,6 +45,23 @@ module type S = sig
val remove : t -> elt -> t
val add_mult : t -> elt -> int -> t
(** [add_mult set x n] adds [n] occurrences of [x] to [set]
@raise Invalid_argument if [n < 0]
@since NEXT_RELEASE *)
val remove_mult : t -> elt -> int -> t
(** [remove_mult set x n] removes at most [n] occurrences of [x] from [set]
@raise Invalid_argument if [n < 0]
@since NEXT_RELEASE *)
val update : t -> elt -> (int -> int) -> t
(** [update set x f] calls [f n] where [n] is the current multiplicity
of [x] in [set] ([0] to indicate its absence); the result of [f n]
is the new multiplicity of [x].
@raise Invalid_argument if [f n < 0]
@since NEXT_RELEASE *)
val min : t -> elt
(** Minimal element w.r.t the total ordering on elements *)