This module provides finite maps that only grow. It is based on the popular Data.Map
balanced-tree representation of maps. Thus scalability is not good for this
implementation. However, there are some interoperability benefits. For example,
after running a parallel computation with a map result, this module can produce a
Map in O(1) without copying, which may be useful downstream.
- data IMap k s v
- newEmptyMap :: Par d s (IMap k s v)
- newMap :: Map k v -> Par d s (IMap k s v)
- newFromList :: (Ord k, Eq v) => [(k, v)] -> Par d s (IMap k s v)
- insert :: (Ord k, Eq v) => k -> v -> IMap k s v -> Par d s ()
- getKey :: Ord k => k -> IMap k s v -> Par d s v
- waitValue :: (Ord k, Eq v) => v -> IMap k s v -> Par d s ()
- waitSize :: Int -> IMap k s v -> Par d s ()
- modify :: forall f a b d s key. (Ord key, LVarData1 f, Show key, Ord a) => IMap key s (f s a) -> key -> Par d s (f s a) -> (f s a -> Par d s b) -> Par d s b
- forEach :: IMap k s v -> (k -> v -> Par d s ()) -> Par d s ()
- forEachHP :: Maybe HandlerPool -> IMap k s v -> (k -> v -> Par d s ()) -> Par d s ()
- withCallbacksThenFreeze :: forall k v b s. Eq b => IMap k s v -> (k -> v -> QPar s ()) -> QPar s b -> QPar s b
- freezeMap :: IMap k s v -> QPar s (Map k v)
- fromIMap :: IMap k Frzn a -> Map k a
- copy :: (Ord k, Eq v) => IMap k s v -> Par d s (IMap k s v)
- traverseMap :: (Ord k, Eq b) => (k -> a -> Par d s b) -> IMap k s a -> Par d s (IMap k s b)
- traverseMap_ :: (Ord k, Eq b) => (k -> a -> Par d s b) -> IMap k s a -> IMap k s b -> Par d s ()
- union :: (Ord k, Eq a) => IMap k s a -> IMap k s a -> Par d s (IMap k s a)
- traverseMapHP :: (Ord k, Eq b) => Maybe HandlerPool -> (k -> a -> Par d s b) -> IMap k s a -> Par d s (IMap k s b)
- traverseMapHP_ :: (Ord k, Eq b) => Maybe HandlerPool -> (k -> a -> Par d s b) -> IMap k s a -> IMap k s b -> Par d s ()
- unionHP :: (Ord k, Eq a) => Maybe HandlerPool -> IMap k s a -> IMap k s a -> Par d s (IMap k s a)
The map datatype itself. Like all other LVars, it has an
s parameter (think
STRef) in addition to the
a parameter that describes the type of elements
in the set.
Performance note: There is only one mutable location in this implementation. Thus it is not a scalable implementation.
|LVarData1 (IMap k)|
|OrderedLVarData1 (IMap k)|
|Foldable (IMap k Trvrsbl)|
|Foldable (IMap k Frzn)|
|Eq (IMap k s v)|
Equality is physical equality, as with
|(Show k, Show a) => Show (IMap k Trvrsbl a)|
For convenience only; the user could define this.
|(Show k, Show a) => Show (IMap k Frzn a)|
|DeepFrz a => DeepFrz (IMap k s a)|
Put a single entry into the map. Strict (WHNF) in the key and value.
As with other container LVars, if a key is inserted multiple times, the values had
better be equal
(==), or a multiple-put error is raised.
Wait for the map to contain a specified key, and return the associated value.
Wait until the map contains a certain value (on any key).
|:: forall f a b d s key . (Ord key, LVarData1 f, Show key, Ord a)|
|=> IMap key s (f s a)|
The key to lookup.
|-> Par d s (f s a)|
Create a new "bottom" element whenever an entry is not present.
|-> (f s a -> Par d s b)|
The computation to apply on the right-hand side of the keyed entry.
|-> Par d s b|
IMaps containing other LVars have some additional capabilities compared to
those containing regular Haskell data. In particular, it is possible to modify
existing entries (monotonically). Further, this
modify function implicitly
inserts a "bottom" element if there is no existing entry for the key.
Unfortunately, that means that this takes another computation for creating new
"bottom" elements for the nested LVars stored inside the
Iteration and callbacks
Add an (asynchronous) callback that listens for all new new key/value pairs added to the map.
|:: Maybe HandlerPool|
optional pool to enroll in
|-> IMap k s v|
Map to listen to
|-> (k -> v -> Par d s ())|
|-> Par d s ()|
Add an (asynchronous) callback that listens for all new key/value pairs added to the map, optionally enrolled in a handler pool.
Register a per-element callback, then run an action in this context, and freeze when all (recursive) invocations of the callback are complete. Returns the final value of the provided action.
Get the exact contents of the map. As with any
quasi-deterministic operation, using
freezeSet may cause your
program to exhibit a limited form of nondeterminism: it will never
return the wrong answer, but it may include synchronization bugs
that can (nondeterministically) cause exceptions.
This Data.Map-based implementation has the special property that
you can retrieve the full set without any
IO, and without
nondeterminism leaking. (This is because the internal order is
fixed for the tree-based representation of maps that Data.Map
Higher-level derived operations
Return a fresh map which will contain strictly more elements than the input. That is, things put in the former go in the latter, but not vice versa.
Establish a monotonic map between the input and output sets. Produce a new result based on each element, while leaving the keys the same.
An imperative-style, in-place version of
traverseMap that takes the output set
as an argument.
Return a new map which will (ultimately) contain everything in either input map. Conflicting entries will result in a multiple put exception.
Alternate versions of derived ops that expose
HandlerPools they create
A variant of
traverseMap that optionally ties the handlers to a pool.
A variant of
traverseMap_ that optionally ties the handlers to a pool.