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Version: 1.6.0

map

Maps from keys to values, where the bindings key/value are ordered by increasing keys.

type t<key, value> = map<key, value>

The type Map.t<key, value> is an alias for map<key,value>.

let empty: <key, value>t<key, value>

The value Map.empty is the empty map. In some contexts, it is useful to annotate it with its type, for example: (Map.empty as map<int, string>).

let get_and_update: <key, value>(_: key) => (_: option<value>) => (_: t<key, value>) => [option<value>, t<key, value>]

The call Map.get_and_update(key, None(), map) returns a copy of the map map without the entry for the key key in map (no change if the key is absent). The call Map.get_and_update(key, Some(value), map) returns a copy of the map map where there is an entry for the key key associated with the value value. In both cases, if there was already a value v bound to key, it is returned as Some(v), otherwise None().

let update: <key, value>(_: key) => (_: option<value>) => (_: t<key, value>) => t<key, value>

The call Map.update(key, None(), map) returns a copy of the map map without the entry for the key key in map (no change if the key is absent). The call Map.update(key, Some(value), map) returns the map map where there is an entry for the key key associated with the value value. In both cases, the value originally bound to key is lost. See Map.get_and_update.

let add: <key, value>(_: key) => (_: value) => (_: t<key, value>) => t<key, value>

The call Map.add(key, value, map) returns a copy of the map where there is a binding of key key to value value. If there is a binding for key in map, then it is lost.

let remove: <key, value>(_: key) => (_: t<key, value>) => t<key, value>

The call Map.remove(key, map) returns a copy of the map map where the binding for key key is absent.

let literal: <key, value>(_: list<[key, value]>) => t<key, value>

The call Map.literal(list([[k1,v1], ..., [kn,vn]])) returns a map from the pairs of key/value in the list. Note: The list must be a literal, not an expression (compile-time list of values).

let of_list: <key, value>(_: list<[key, value]>) => t<key, value>

The call Map.of_list(bindings) returns a map from the pairs of key/value in the list bindings. Note: Use Map.literal instead if using a literal list.

let size: <key, value>(_: t<key, value>) => nat

The call Map.size(map) evaluates in the number of entries in the map map.

let mem: <key, value>(_: key) => (_: t<key, value>) => bool

The call Map.mem(key, map) is true if, and only if, the key key is in the map map.

let find_opt: <key, value>(_: key) => (_: t<key, value>) => option<value>

The call Map.find_opt(key, map) returns None() if the key key is present in the map map; otherwise, it is Some(v), where v is the value associated to key in map.

let find: <key, value>(_: key) => (_: t<key, value>) => value

The call Map.find(key, map) returns the value associated to key in map. If the key is absent, the execution fails with the string "MAP FIND".

let fold: <key, value, acc>(_: (_: [acc, [key, value]]) => acc) => (_: t<key, value>) => (_: acc) => acc

The call Map.fold(f, map, init) is f (... f (f (init, [k1,v1]), [k2,v2]), ..., [kn,vn]) where [k1,v1], [k2,v2], ..., [kn,vn] are the bindings in the map map, in increasing order of the keys k1, k2, ..., and kn.

let iter: <key, value>(_: (_: [key, value]) => unit) => (_: t<key, value>) => unit

The call Map.iter(f, map) is {f (k1,v1); (k2,v2); ...; f (kn,vn);}.

let map: <key, value, new_value>(_: (_: [key, value]) => new_value) => (_: t<key, value>) => t<key, new_value>

The call Map.map(f, m), where the map m contains the bindings [k1,v1], [k2,v2], ..., and [kn,vn] in increasing order of the keys, is the map containing the bindings [k1, f (k1,v1)], [k2, f (k2,v2)], ..., [kn, f (kn,vn)].