add x y m returns a map containing the same bindings as
m, plus a binding of x to y. If x was already bound
in m to a value that is physically equal to y,
m is returned unchanged (the result of the function is
then physically equal to m). Otherwise, the previous binding
of x in m disappears.
update x f m returns a map containing the same bindings as
m, except for the binding of x. Depending on the value of
y where y is f (find_opt x m), the binding of x is
added, removed or updated. If y is None, the binding is
removed if it exists; otherwise, if y is Some z then x
is associated to z in the resulting map. If x 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).
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).
merge f m1 m2 computes a map whose keys is a subset of 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 (find_opt x m1) (find_opt x m2)
for any key x, provided that f None None = None.
union f m1 m2 computes a map whose keys is the union of 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' None None = Nonef' (Some v) None = Some vf' None (Some v) = Some vf' (Some v1) (Some v2) = f v1 v2Total ordering between maps. The first argument is a total ordering used to compare data associated with equal keys in the two maps.
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.
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.
fold f m a computes (f kN dN ... (f k1 d1 a)...),
where k1 ... kN are the keys of all bindings in m
(in increasing order), and d1 ... dN are the associated data.
filter p m returns the map with all the bindings in m
that satisfy predicate p. If p satisfies every binding in m,
m is returned unchanged (the result of the function is then
physically equal to m)
partition p m returns a pair of maps (m1, m2), where
m1 contains all the bindings of s that satisfy the
predicate p, and m2 is the map with all the bindings of
s that do not satisfy p.
Return the list of all bindings of the given map.
The returned list is sorted in increasing order with respect
to the ordering Ord.compare, where Ord is the argument
given to Map.Make.
Return the smallest binding of the given map
(with respect to the Ord.compare ordering), or raise
Not_found if the map is empty.
Return the smallest binding of the given map
(with respect to the Ord.compare ordering), or None
if the map is empty.
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.
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.
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.
find_opt x m returns Some v if the current binding of x
in m is v, or None if no such binding exists.
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.
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.
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.
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.