module Make:
Functor building an implementation of the set structure
given a totally ordered type.
type
elt
The type of the set elements.
type
t
The type of sets.
val empty : t
The empty set.
val is_empty : t -> bool
Test whether a set is empty or not.
val mem : elt -> t -> bool
mem x s
tests whether x
belongs to the set s
.
val add : elt -> t -> t
add x s
returns a set containing all elements of s
,
plus x
. If x
was already in s
, s
is returned unchanged.
val singleton : elt -> t
singleton x
returns the one-element set containing only x
.
val remove : elt -> t -> t
remove x s
returns a set containing all elements of s
,
except x
. If x
was not in s
, s
is returned unchanged.
val union : t -> t -> t
Set union.
val inter : t -> t -> t
Set intersection.
val diff : t -> t -> t
Set difference.
val compare : t -> t -> int
Total ordering between sets. Can be used as the ordering function
for doing sets of sets.
val equal : t -> t -> bool
equal s1 s2
tests whether the sets s1
and s2
are
equal, that is, contain equal elements.
val subset : t -> t -> bool
subset s1 s2
tests whether the set s1
is a subset of
the set s2
.
val iter : (elt -> unit) -> t -> unit
iter f s
applies f
in turn to all elements of s
.
The elements of s
are presented to f
in increasing order
with respect to the ordering over the type of the elements.
val fold : (elt -> 'a -> 'a) -> t -> 'a -> 'a
fold f s a
computes (f xN ... (f x2 (f x1 a))...)
,
where x1 ... xN
are the elements of s
, in increasing order.
val for_all : (elt -> bool) -> t -> bool
for_all p s
checks if all elements of the set
satisfy the predicate p
.
val exists : (elt -> bool) -> t -> bool
exists p s
checks if at least one element of
the set satisfies the predicate p
.
val filter : (elt -> bool) -> t -> t
filter p s
returns the set of all elements in s
that satisfy predicate p
.
val partition : (elt -> bool) -> t -> t * t
partition p s
returns a pair of sets (s1, s2)
, where
s1
is the set of all the elements of s
that satisfy the
predicate p
, and s2
is the set of all the elements of
s
that do not satisfy p
.
val cardinal : t -> int
Return the number of elements of a set.
val elements : t -> elt list
Return the list of all elements of the given set.
The returned list is sorted in increasing order with respect
to the ordering
Ord.compare
, where
Ord
is the argument
given to
Set.Make
.
val min_elt : t -> elt
Return the smallest element of the given set
(with respect to the Ord.compare
ordering), or raise
Not_found
if the set is empty.
val max_elt : t -> elt
Same as
Set.S.min_elt
, but returns the largest element of the
given set.
val choose : t -> elt
Return one element of the given set, or raise Not_found
if
the set is empty. Which element is chosen is unspecified,
but equal elements will be chosen for equal sets.
val split : elt -> t -> t * bool * t
split x s
returns a triple (l, present, r)
, where
l
is the set of elements of s
that are
strictly less than x
;
r
is the set of elements of s
that are
strictly greater than x
;
present
is false
if s
contains no element equal to x
,
or true
if s
contains an element equal to x
.
val find : elt -> t -> elt
find x s
returns the element of s
equal to x
(according
to Ord.compare
), or raise Not_found
if no such element
exists.
Since 4.01.0
val of_list : elt list -> t
of_list l
creates a set from a list of elements.
This is usually more efficient than folding add
over the list,
except perhaps for lists with many duplicated elements.
Since 4.02.0