Module Hstring

module Hstring: sig .. end

Hash-consed strings

Hash-consing is a technique to share values that are structurally equal. More details on Wikipedia and here.

This module provides an easy way to use hash-consing for strings.

type t = string Hashcons.hash_consed

The type of Hash-consed string

val make : string -> t

make s builds ans returns a hash-consed string from s.

val view : t -> string

view hs returns the string corresponding to hs.

val equal : t -> t -> bool

equal x y returns true if x and y are the same hash-consed string (constant time).

val compare : t -> t -> int

compares x y returns 0 if x and y are equal, and is unspecified otherwise but provides a total ordering on hash-consed strings.

val hash : t -> int

hash x returns the integer (hash) associated to x.

val empty : t

the empty ("") hash-consed string.

val list_assoc : t -> (t * 'a) list -> 'a

list_assoc x l returns the element associated with x in the list of pairs l.
Raises Not_found if there is no value associated with x in the list l.

val list_mem_assoc : t -> (t * 'a) list -> bool

Same as Hstring.list_assoc, but simply returns true if a binding exists, and false if no bindings exist for the given key.

val list_mem : t -> t list -> bool

list_mem x l is true if and only if x is equal to an element of l.

val list_mem_couple : t * t -> (t * t) list -> bool

list_mem_couple (x,y) l is true if and only if (x,y) is equal to an element of l.

val compare_list : t list -> t list -> int

compare_list l1 l2 returns 0 if and only if l1 is equal to l2.

val print : Format.formatter -> t -> unit

Prints a list of hash-consed strings on a formatter.

module H: Hashtbl.S  with type key = t

Hash-tables indexed by hash-consed strings

module HSet: Set.S  with type elt = t

Sets of hash-consed strings

module HMap: Map.S  with type key = t

Maps indexed by hash-consed strings