Module BatSet


module BatSet: sig .. end
Sets over ordered types.

This module implements the set data structure, given a total ordering function over the set elements. All operations over sets are purely applicative (no side-effects). The implementation uses balanced binary trees, and is therefore reasonably efficient: insertion and membership take time logarithmic in the size of the set, for instance.

Note OCaml, Batteries Included, provides two implementations of sets: polymorphic sets and functorized sets. Functorized sets (see BatSet.S and BatSet.Make) are slightly more complex to use but offer stronger type-safety. Polymorphic sets make it easier to shoot yourself in the foot. In case of doubt, you should use functorized sets.

The functorized set implementation is built upon Stdlib's Set module, but provides the complete interface.
Author(s): Xavier Leroy, Nicolas Cannasse, Markus Mottl, David Rajchenbach-Teller



Functorized Sets


module type OrderedType = BatInterfaces.OrderedType
Input signature of the functor Set.Make.
module type S = sig .. end
Output signature of the functor Set.Make.
module StringSet: S  with type elt = String.t
A set of strings.
module IStringSet: S  with type elt = String.t
A set of strings.
module NumStringSet: S  with type elt = String.t
A set of strings.
module RopeSet: S  with type elt = BatRope.t
A set of ropes.
module IRopeSet: S  with type elt = BatRope.t
A set of ropes.
module IntSet: S  with type elt = BatInt.t
A set of integers.
module CharSet: S  with type elt = Char.t
A set of characters.
module Make: 
functor (Ord : OrderedType) -> S with type elt = Ord.t
Functor building an implementation of the set structure given a totally ordered type.

Polymorphic sets

The definitions below describe the polymorphic set interface.

They are similar in functionality to the functorized BatSet.Make module, but the compiler cannot ensure that sets using different element ordering have different types: the responsibility of not mixing non-sensical comparison functions together is to the programmer. If in doubt, you should rather use the BatSet.Make functor for additional safety.

type 'a t 
The type of sets.
include BatEnum.Enumerable
include BatInterfaces.Mappable
val empty : 'a t
The empty set, using compare as comparison function
val create : ('a -> 'a -> int) -> 'a t
Creates a new empty set, using the provided function for key comparison.
val is_empty : 'a t -> bool
Test whether a set is empty or not.
val singleton : ?cmp:('a -> 'a -> int) -> 'a -> 'a t
Creates a new set with the single given element in it.
val mem : 'a -> 'a t -> bool
mem x s tests whether x belongs to the set s.
val add : 'a -> 'a t -> 'a 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 remove : 'a -> 'a t -> 'a 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 : 'a t -> 'a t -> 'a t
union s t returns the union of s and t - the set containing all elements in either s and t. The returned set uses t's comparison function. The current implementation works better for small s.
val intersect : 'a t -> 'a t -> 'a t
intersect s t returns a new set of those elements that are in both s and t. The returned set uses s's comparison function.
val diff : 'a t -> 'a t -> 'a t
diff s t returns the set of all elements in s but not in t. The returned set uses s's comparison function.
val subset : 'a t -> 'a t -> bool
subset a b returns true if a is a subset of b. O(|a|).
val iter : ('a -> unit) -> 'a 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 map : ('a -> 'b) -> 'a t -> 'b t
map f x creates a new set with elements f a0, f a1... f aN, where a0, a1, ..., aN are the values contained in x
val filter : ('a -> bool) -> 'a t -> 'a t
filter p s returns the set of all elements in s that satisfy predicate p.
val filter_map : ('a -> 'b option) -> 'a t -> 'b t
filter_map f m combines the features of filter and map. It calls calls f a0, f a1, f aN where a0,a1..an are the elements of m and returns the set of pairs bi such as f ai = Some bi (when f returns None, the corresponding element of m is discarded).
val fold : ('a -> 'b -> 'b) -> 'a t -> 'b -> 'b
fold f s a computes (f xN ... (f x1 (f x0 a))...), where x0,x1..xN are the elements of s, in increasing order.
val exists : ('a -> bool) -> 'a t -> bool
exists p s checks if at least one element of the set satisfies the predicate p.
val for_all : ('a -> bool) -> 'a t -> bool
Returns whether the given predicate applies to all elements in the set
val partition : ('a -> bool) -> 'a t -> 'a t * 'a t
returns two disjoint subsets, those that satisfy the given predicate and those that don't
val split : 'a -> 'a t -> 'a t * bool * 'a 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 cardinal : 'a t -> int
Return the number of elements of a set.
val min_elt : 'a t -> 'a
returns the smallest element of the set. Raises Invalid_argument if given an empty set.
val max_elt : 'a t -> 'a
returns the largest element of the set. Raises Invalid_argument if given an empty set.
val choose : 'a t -> 'a
returns an arbitrary (but deterministic) element of the given set. Raises Invalid_argument if given an empty set.
val pop : 'a t -> 'a * 'a t
returns one element of the set and the set without that element. Raises Not_found if given an empty set
val enum : 'a t -> 'a BatEnum.t
Return an enumeration of all elements of the given set. The returned enumeration is sorted in increasing order with respect to the ordering of this set.
val of_enum : 'a BatEnum.t -> 'a t
val of_enum_cmp : cmp:('a -> 'a -> int) -> 'a BatEnum.t -> 'a t
val of_list : 'a list -> 'a t
builds a set from the given list, using the default comparison function

Boilerplate code


Printing

val print : ?first:string ->
?last:string ->
?sep:string ->
('a BatInnerIO.output -> 'b -> unit) ->
'a BatInnerIO.output -> 'b t -> unit