module Map: Map.S with type key = string;
type key;
The type of the map keys.
type t(+'a);
The type of maps from type key to type 'a.
let empty: t('a);
The empty map.
let is_empty: t('a) => bool;
Test whether a map is empty or not.
let mem: (key, t('a)) => bool;
mem x m returns true if m contains a binding for x,
and false otherwise.
let add: (key, 'a, t('a)) => t('a);
add key data m returns a map containing the same bindings as
m, plus a binding of key to data. If key was already bound
in m to a value that is physically equal to data,
m is returned unchanged (the result of the function is
then physically equal to m). Otherwise, the previous binding
of key in m disappears.
let update: (key, option('a) => option('a), t('a)) => t('a);
update key f m returns a map containing the same bindings as
m, except for the binding of key. Depending on the value of
y where y is f (find_opt key m), the binding of key is
added, removed or updated. If y is None, the binding is
removed if it exists; otherwise, if y is Some z then key
is associated to z in the resulting map. If key was already
bound in m to a value that is physically equal to z, m
is returned unchanged (the result of the function is then
physically equal to m).
let singleton: (key, 'a) => t('a);
singleton x y returns the one-element map that contains a binding
y for x.
let remove: (key, t('a)) => t('a);
remove x m returns a map containing the same bindings as
m, except for x which is unbound in the returned map.
If x was not in m, m is returned unchanged
(the result of the function is then physically equal to m).
let merge:
((key, option('a), option('b)) => option('c), t('a), t('b)) => t('c);
merge f m1 m2 computes a map whose keys are a subset of the keys of
m1 and of m2. The presence of each such binding, and the
corresponding value, is determined with the function f.
In terms of the find_opt operation, we have
find_opt x (merge f m1 m2) = f x (find_opt x m1) (find_opt x m2)
for any key x, provided that f x None None = None.
let union: ((key, 'a, 'a) => option('a), t('a), t('a)) => t('a);
union f m1 m2 computes a map whose keys are a subset of the keys
of m1 and of m2. When the same binding is defined in both
arguments, the function f is used to combine them.
This is a special case of merge: union f m1 m2 is equivalent
to merge f' m1 m2, where
f' _key None None = Nonef' _key (Some v) None = Some vf' _key None (Some v) = Some vf' key (Some v1) (Some v2) = f key v1 v2let compare: (('a, 'a) => int, t('a), t('a)) => int;
Total ordering between maps. The first argument is a total ordering used to compare data associated with equal keys in the two maps.
let equal: (('a, 'a) => bool, t('a), t('a)) => bool;
equal cmp m1 m2 tests whether the maps m1 and m2 are
equal, that is, contain equal keys and associate them with
equal data. cmp is the equality predicate used to compare
the data associated with the keys.
let iter: ((key, 'a) => unit, t('a)) => unit;
iter f m applies f to all bindings in map m.
f receives the key as first argument, and the associated value
as second argument. The bindings are passed to f in increasing
order with respect to the ordering over the type of the keys.
let fold: ((key, 'a, 'b) => 'b, t('a), 'b) => 'b;
fold f m init computes (f kN dN ... (f k1 d1 init)...),
where k1 ... kN are the keys of all bindings in m
(in increasing order), and d1 ... dN are the associated data.
let for_all: ((key, 'a) => bool, t('a)) => bool;
for_all f m checks if all the bindings of the map
satisfy the predicate f.
let exists: ((key, 'a) => bool, t('a)) => bool;
exists f m checks if at least one binding of the map
satisfies the predicate f.
let filter: ((key, 'a) => bool, t('a)) => t('a);
filter f m returns the map with all the bindings in m
that satisfy predicate p. If every binding in m satisfies f,
m is returned unchanged (the result of the function is then
physically equal to m)
let filter_map: ((key, 'a) => option('b), t('a)) => t('b);
filter_map f m applies the function f to every binding of
m, and builds a map from the results. For each binding
(k, v) in the input map:
f k v is None then k is not in the result,f k v is Some v' then the binding (k, v')
is in the output map.For example, the following function on maps whose values are lists
filter_map
(fun _k li -> match li with [] -> None | _::tl -> Some tl)
m
drops all bindings of m whose value is an empty list, and pops
the first element of each value that is non-empty.
let partition: ((key, 'a) => bool, t('a)) => (t('a), t('a));
partition f m returns a pair of maps (m1, m2), where
m1 contains all the bindings of m that satisfy the
predicate f, and m2 is the map with all the bindings of
m that do not satisfy f.
let cardinal: t('a) => int;
Return the number of bindings of a map.
let bindings: t('a) => list((key, 'a));
Return the list of all bindings of the given map.
The returned list is sorted in increasing order of keys with respect
to the ordering Ord.compare, where Ord is the argument
given to Map.Make.
let min_binding: t('a) => (key, 'a);
Return the binding with the smallest key in a given map
(with respect to the Ord.compare ordering), or raise
Not_found if the map is empty.
let min_binding_opt: t('a) => option((key, 'a));
Return the binding with the smallest key in the given map
(with respect to the Ord.compare ordering), or None
if the map is empty.
let max_binding: t('a) => (key, 'a);
Same as Map.S.min_binding, but returns the binding with
the largest key in the given map.
let max_binding_opt: t('a) => option((key, 'a));
Same as Map.S.min_binding_opt, but returns the binding with
the largest key in the given map.
let choose: t('a) => (key, 'a);
Return one binding of the given map, or raise Not_found if
the map is empty. Which binding is chosen is unspecified,
but equal bindings will be chosen for equal maps.
let choose_opt: t('a) => option((key, 'a));
Return one binding of the given map, or None if
the map is empty. Which binding is chosen is unspecified,
but equal bindings will be chosen for equal maps.
let split: (key, t('a)) => (t('a), option('a), t('a));
split x m returns a triple (l, data, r), where
l is the map with all the bindings of m whose key
is strictly less than x;
r is the map with all the bindings of m whose key
is strictly greater than x;
data is None if m contains no binding for x,
or Some v if m binds v to x.
let find: (key, t('a)) => 'a;
find x m returns the current value of x in m,
or raises Not_found if no binding for x exists.
let find_opt: (key, t('a)) => option('a);
find_opt x m returns Some v if the current value of x
in m is v, or None if no binding for x exists.
let find_first: (key => bool, t('a)) => (key, 'a);
find_first f m, where f is a monotonically increasing function,
returns the binding of m with the lowest key k such that f k,
or raises Not_found if no such key exists.
For example, find_first (fun k -> Ord.compare k x >= 0) m will return
the first binding k, v of m where Ord.compare k x >= 0
(intuitively: k >= x), or raise Not_found if x is greater than
any element of m.
let find_first_opt: (key => bool, t('a)) => option((key, 'a));
find_first_opt f m, where f is a monotonically increasing
function, returns an option containing the binding of m with the
lowest key k such that f k, or None if no such key exists.
let find_last: (key => bool, t('a)) => (key, 'a);
find_last f m, where f is a monotonically decreasing function,
returns the binding of m with the highest key k such that f k,
or raises Not_found if no such key exists.
let find_last_opt: (key => bool, t('a)) => option((key, 'a));
find_last_opt f m, where f is a monotonically decreasing
function, returns an option containing the binding of m with
the highest key k such that f k, or None if no such key
exists.
let map: ('a => 'b, t('a)) => t('b);
map f m returns a map with same domain as m, where the
associated value a of all bindings of m has been
replaced by the result of the application of f to a.
The bindings are passed to f in increasing order
with respect to the ordering over the type of the keys.
let mapi: ((key, 'a) => 'b, t('a)) => t('b);
Same as Map.S.map, but the function receives as arguments both the
key and the associated value for each binding of the map.
let to_seq: t('a) => Seq.t((key, 'a));
Iterate on the whole map, in ascending order of keys
let to_rev_seq: t('a) => Seq.t((key, 'a));
Iterate on the whole map, in descending order of keys
let to_seq_from: (key, t('a)) => Seq.t((key, 'a));
to_seq_from k m iterates on a subset of the bindings of m,
in ascending order of keys, from key k or above.
let add_seq: (Seq.t((key, 'a)), t('a)) => t('a);
Add the given bindings to the map, in order.
let of_seq: Seq.t((key, 'a)) => t('a);
Build a map from the given bindings