Library
Module
Module type
Parameter
Class
Class type
A SET_MAKER
is a functor that instantiates CACHE_SET
s based on a given type and its associated hash function.
A Mutable structure akin to a set, but with a size bound. Note that, different caches have different policies towards the size bounds: some uphold the bound strictly, some treat the bound as a suggestion. In addition, some caches count their elements somewhat sloppily.
In general, the caches of ringo are intended to be used in settings that do not require strict, by-the-number, extremely-predictable behaviors.
See Ringo
(or Functors
) for more information.
val create : int -> t
create n
creates a unit-cache with a size-bound of n
. Remember that the size-bound is not upheld strictly by all caches.
add c v
adds the value v
to the cache c
. This may or may not cause another element to be removed from the cache, depending on the number of elements already present in the cache c
, the size-bound of the cache c
, and the policy of the cache c
towards its size-bound.
Note that after the add c v
call returns, v
is the most recent element in the cache. This is true whether or not the element was already in the cache before the call. This is true for whichever replacement policy (see Ringo.replacement
) the cache has.
If v
is already present in c
, and the accounting policy of the cache is Sloppy
, the element may or may not count twice towards the size bound for some time. On the other hand, if the cache accounting is Precise
then the element v
only counts once. See Ringo.accounting
for more details.
fold f c init
folds the function f
and value init
over the elements of c
from newest to oldest.
Note that for caches with a Weak
overflow policy, this function may fold over a subset of the elements of c
. See Ringo
(or Functors
) for more details.
fold_oldest_first
is like fold
but in reversed order: oldest elements of c
first. This function has the same limitation as fold
.
mem c v
is true
if v
is present in c
. It is false
otherwise.
Note that the in caches with a non-FIFO
replacement policy, this may have a side effect on the v
element. Specifically, in those caches, it might make it less likely to be removed when supernumerary elements are inserted.
remove c v
removes the element v
from c
. If v
is not present in c
, it does nothing.
Note that in caches with a Sloppy
accounting policy, removed elements can still count towards the size bound for some time. On the other hand, if the cache's accounting policy is Precise
then the element immediately stops counting towards the size bound.
filter c f
removes all the elements v
such that f v = false
.
Note that in caches with a Sloppy
accounting policy, removed elements can still count towards the size bound for some time.
val length : t -> int
length c
is the number of elements present in c
.
val capacity : t -> int
capacity c
is the number of bindings c
can hold: capacity (create n) = n
val clear : t -> unit
clear c
removes all elements from c
.