Type for values, this is a divergence from Stdlib's Map, but becomes equivalent to it when using MAP, which is just MAP_WITH_VALUE with type 'a value = 'a. On the other hand, it allows defining maps with fixed values, which is useful for hash-consing.
Returns a map with the element removed, O(log(n)) complexity. Returns a physically equal map if the element is absent.
val pop_unsigned_minimum : 'at->(key * 'avalue * 'at) option
pop_unsigned_minimum m returns None if is_empty m, or Some(key,value,m') where (key,value) = unsigned_min_binding m and m' = remove m key. O(log(n)) complexity. Uses the unsigned order on KEY.to_int.
val pop_unsigned_maximum : 'at->(key * 'avalue * 'at) option
pop_unsigned_maximum m returns None if is_empty m, or Some(key,value,m') where (key,value) = unsigned_max_binding m and m' = remove m key. O(log(n)) complexity. Uses the unsigned order on KEY.to_int.
insert key f map modifies or insert an element of the map; f takes None if the value was not previously bound, and Some old where old is the previously bound value otherwise. The function preserves physical equality when possible. O(log(n)) complexity. Preserves physical equality if the new value is physically equal to the old.
val update : key->('avalue option->'avalue option)->'at->'at
update key f map modifies, insert, or remove an element from the map; f takes None if the value was not previously bound, and Some old where old is the previously bound value otherwise. The function preserves physical equality when possible. It returns None if the element should be removed O(log(n)) complexity. Preserves physical equality if the new value is physically equal to the old.
Unconditionally adds a value in the map (independently from whether the old value existed). O(log(n)) complexity. Preserves physical equality if the new value is physically equal to the old.
val fold_on_nonequal_inter :
(key->'avalue->'avalue->'acc->'acc)->'at->'at->'acc->'acc
fold_on_nonequal_inter f m1 m2 acc returns f key_n value1_n value2n (... (f key_1 value1_1 value2_1 acc)) where (key_1, value1_1, value2_1) ... (key_n, value1_n, value2_n) are the bindings that exist in both maps (m1 ∩ m2) whose values are physically different. Calls to f are performed in the unsigned order of KEY.to_int.
val fold_on_nonequal_union :
(key->'avalue option->'avalue option->'acc->'acc)->'at->'at->'acc->'acc
fold_on_nonequal_union f m1 m2 acc returns f key_n value1_n value2n (... (f key_1 value1_1 value2_1 acc)) where (key_1, value1_1, value2_1) ... (key_n, value1_n, value2_n) are the bindings that exists in either map (m1 ∪ m2) whose values are physically different. Calls to f.f are performed in the unsigned order of KEY.to_int.
Returns true if the predicate holds on all map bindings. Short-circuiting. f is called in increasing unsigned order of KEY.to_int.
In the following, the *no_share function allows taking arguments of different types (but cannot share subtrees of the map), while the default functions attempt to preserve and benefit from sharing the subtrees (using physical equality to detect sharing).
map f m returns a map where the value bound to each key is replaced by f value. The subtrees for which the returned value is physically the same (i.e. f key value == value for all the keys in the subtree) are guaranteed to be physically equal to the original subtree. O(n) complexity. f is called in increasing unsigned order of KEY.to_int.
map_no_share f m returns a map where the value bound to each key is replaced by f value. O(n) complexity. f is called in increasing unsigned order of KEY.to_int.
mapi f m returns a map where the value bound to each key is replaced by f key value. The subtrees for which the returned value is physically the same (i.e. f key value == value for all the keys in the subtree) are guaranteed to be physically equal to the original subtree. O(n) complexity. f is called in increasing unsigned order of KEY.to_int.
mapi_no_share f m returns a map where the value bound to each key is replaced by f key value. O(n) complexity. f is called in increasing unsigned order of KEY.to_int.
filter_map m f returns a map where the value bound to each key is removed (if f key value returns None), or is replaced by v ((if f key value returns Some v). The subtrees for which the returned value is physically the same (i.e. f key value = Some v with value == v for all the keys in the subtree) are guaranteed to be physically equal to the original subtree. O(n) complexity. f is called in increasing unsigned order of KEY.to_int.
val filter_map_no_share : (key->'avalue->'bvalue option)->'at->'bt
filter_map m f returns a map where the value bound to each key is removed (if f key value returns None), or is replaced by v ((if f key value returns Some v). O(n) complexity. f is called in increasing unsigned order of KEY.to_int.
Operations on pairs of maps
The following functions combine two maps. It is key for the performance, when we have large maps who share common subtrees, not to visit the nodes in these subtrees. Hence, we have specialized versions of these functions that assume properties of the function parameter (reflexive relation, idempotent operation, etc.)
When we cannot enjoy these properties, our functions explicitly say so (with a nonreflexive or nonidempotent prefix). The names are a bit long, but having these names avoids using an ineffective code by default, by forcing to know and choose between the fast and slow version.
It is also important to not visit a subtree when there merging this subtree with Empty; hence we provide union and inter operations.
val reflexive_same_domain_for_all2 :
(key->'avalue->'avalue-> bool)->'at->'at->
bool
reflexive_same_domain_for_all2 f map1 map2 returns true if map1 and map2 have the same keys, and f key value1 value2 returns true for each mapping pair of keys. We assume that f is reflexive (i.e. f key value value returns true) to avoid visiting physically equal subtrees of map1 and map2. The complexity is O(log(n)*Delta) where Delta is the number of different keys between map1 and map2.
val nonreflexive_same_domain_for_all2 :
(key->'avalue->'bvalue-> bool)->'at->'bt->
bool
nonreflexive_same_domain_for_all2 f map1 map2 returns true if map1 and map2 have the same keys, and f key value1 value2 returns true for each mapping pair of keys. The complexity is O(min(|map1|,|map2|)).
val reflexive_subset_domain_for_all2 :
(key->'avalue->'avalue-> bool)->'at->'at->
bool
reflexive_subset_domain_for_all2 f map1 map2 returns true if all the keys of map1 also are in map2, and f key (find map1
key) (find map2 key) returns true when both keys are present in the map. We assume that f is reflexive (i.e. f key value
value returns true) to avoid visiting physically equal subtrees of map1 and map2. The complexity is O(log(n)*Delta) where Delta is the number of different keys between map1 and map2.
idempotent_union f map1 map2 returns a map whose keys is the union of the keys of map1 and map2. f is used to combine the values a key is mapped in both maps. We assume that f is idempotent (i.e. f key value value == value) to avoid visiting physically equal subtrees of map1 and map2, and also to preserve physical equality of the subtreess in that case. The complexity is O(log(n)*Delta) where Delta is the number of different keys between map1 and map2. f is called in increasing unsigned order of KEY.to_int. f is never called on physically equal values.
idempotent_inter f map1 map2 returns a map whose keys is the intersection of the keys of map1 and map2. f is used to combine the values a key is mapped in both maps. We assume that f is idempotent (i.e. f key value value == value) to avoid visiting physically equal subtrees of map1 and map2, and also to preserve physical equality of the subtrees in that case. The complexity is O(log(n)*Delta) where Delta is the number of different keys between map1 and map2. f is called in increasing unsigned order of KEY.to_int!. f is never called on physically equal values.
nonidempotent_inter_no_share f map1 map2 returns a map whose keys is the intersection of the keys of map1 and map2. f is used to combine the values a key is mapped in both maps. f does not need to be idempotent, which imply that we have to visit physically equal subtrees of map1 and map2. The complexity is O(log(n)*min(|map1|,|map2|)). f is called in increasing unsigned order of KEY.to_int. f is called on every shared binding.
val idempotent_inter_filter :
(key->'avalue->'avalue->'avalue option)->'at->'at->'at
idempotent_inter_filter f m1 m2 is like idempotent_inter (assuming idempotence, using and preserving physically equal subtrees), but it also removes the key->value bindings for which f returns None.
val slow_merge :
(key->'avalue option->'bvalue option->'cvalue option)->'at->'bt->'ct
slow_merge f m1 m2 returns a map whose keys are a subset of the keys of m1 and m2. The f function is used to combine keys, similarly to the Map.merge function. This funcion has to traverse all the bindings in m1 and m2; its complexity is O(|m1|+|m2|). Use one of faster functions above if you can.