Base.Stack
module type S = sig ... end
include S
include Sexplib0.Sexpable.S1 with type 'a t := 'a t
val t_of_sexp : (Sexplib0.Sexp.t -> 'a) -> Sexplib0.Sexp.t -> 'a t
val sexp_of_t : ('a -> Sexplib0.Sexp.t) -> 'a t -> Sexplib0.Sexp.t
val t_sexp_grammar : 'a Sexplib0.Sexp_grammar.t -> 'a t Sexplib0.Sexp_grammar.t
include Invariant.S1 with type 'a t := 'a t
val invariant : ('a -> unit) -> 'a t -> unit
fold
, iter
, find
, and find_map
visit the elements in order from the top of the stack to the bottom. to_list
and to_array
return the elements in order from the top of the stack to the bottom.
Iteration functions (iter
, fold
, etc.) have unspecified behavior (although they should still be memory-safe) when the stack is mutated while they are running (e.g. by having the passed-in function call push
or pop
on the stack).
include Container.S1 with type 'a t := 'a t
val mem : 'a t -> 'a -> equal:('a -> 'a -> bool) -> bool
Checks whether the provided element is there, using equal
.
val length : 'a t -> int
val is_empty : 'a t -> bool
val iter : 'a t -> f:('a -> unit) -> unit
val fold : 'a t -> init:'acc -> f:('acc -> 'a -> 'acc) -> 'acc
fold t ~init ~f
returns f (... f (f (f init e1) e2) e3 ...) en
, where e1..en
are the elements of t
fold_result t ~init ~f
is a short-circuiting version of fold
that runs in the Result
monad. If f
returns an Error _
, that value is returned without any additional invocations of f
.
val fold_until :
'a t ->
init:'acc ->
f:('acc -> 'a -> ('acc, 'final) Container.Continue_or_stop.t) ->
finish:('acc -> 'final) ->
'final
fold_until t ~init ~f ~finish
is a short-circuiting version of fold
. If f
returns Stop _
the computation ceases and results in that value. If f
returns Continue _
, the fold will proceed. If f
never returns Stop _
, the final result is computed by finish
.
Example:
type maybe_negative =
| Found_negative of int
| All_nonnegative of { sum : int }
(** [first_neg_or_sum list] returns the first negative number in [list], if any,
otherwise returns the sum of the list. *)
let first_neg_or_sum =
List.fold_until ~init:0
~f:(fun sum x ->
if x < 0
then Stop (Found_negative x)
else Continue (sum + x))
~finish:(fun sum -> All_nonnegative { sum })
;;
let x = first_neg_or_sum [1; 2; 3; 4; 5]
val x : maybe_negative = All_nonnegative {sum = 15}
let y = first_neg_or_sum [1; 2; -3; 4; 5]
val y : maybe_negative = Found_negative -3
val exists : 'a t -> f:('a -> bool) -> bool
Returns true
if and only if there exists an element for which the provided function evaluates to true
. This is a short-circuiting operation.
val for_all : 'a t -> f:('a -> bool) -> bool
Returns true
if and only if the provided function evaluates to true
for all elements. This is a short-circuiting operation.
val count : 'a t -> f:('a -> bool) -> int
Returns the number of elements for which the provided function evaluates to true.
val sum :
(module Container.Summable with type t = 'sum) ->
'a t ->
f:('a -> 'sum) ->
'sum
Returns the sum of f i
for all i
in the container.
val find : 'a t -> f:('a -> bool) -> 'a option
Returns as an option
the first element for which f
evaluates to true.
val find_map : 'a t -> f:('a -> 'b option) -> 'b option
Returns the first evaluation of f
that returns Some
, and returns None
if there is no such element.
val to_list : 'a t -> 'a list
val to_array : 'a t -> 'a array
val min_elt : 'a t -> compare:('a -> 'a -> int) -> 'a option
Returns a minimum (resp maximum) element from the collection using the provided compare
function, or None
if the collection is empty. In case of a tie, the first element encountered while traversing the collection is returned. The implementation uses fold
so it has the same complexity as fold
.
val max_elt : 'a t -> compare:('a -> 'a -> int) -> 'a option
val of_list : 'a list -> 'a t
of_list l
returns a stack whose top is the first element of l
and bottom is the last element of l
.
val create : unit -> _ t
create ()
returns an empty stack.
val singleton : 'a -> 'a t
singleton a
creates a new stack containing only a
.
val push : 'a t -> 'a -> unit
push t a
adds a
to the top of stack t
.
val pop : 'a t -> 'a option
pop t
removes and returns the top element of t
as Some a
, or returns None
if t
is empty.
val pop_exn : 'a t -> 'a
val top : 'a t -> 'a option
top t
returns Some a
, where a
is the top of t
, unless is_empty t
, in which case top
returns None
.
val top_exn : 'a t -> 'a
val clear : _ t -> unit
clear t
discards all elements from t
.
val until_empty : 'a t -> ('a -> unit) -> unit
until_empty t f
repeatedly pops an element a
off of t
and runs f a
, until t
becomes empty. It is fine if f
adds more elements to t
, in which case the most-recently-added element will be processed next.
filter_map t ~f
creates a new stack with only the elements for which f
returns Some
filter t ~f
creates a new stack with only the elements that satisfy f
.
val filter_inplace : 'a t -> f:('a -> bool) -> unit
filter_inplace t ~f
removes all elements of t
that don't satisfy f
.
val capacity : _ t -> int
capacity t
returns the length of the array backing t
.
val set_capacity : _ t -> int -> unit
set_capacity t capacity
sets the length of the array backing t
to max capacity
(length t)
. To shrink as much as possible, do set_capacity t 0
.