Control.Wire.TimedMap

This module implements a map, where each key has a timestamp. It maintains a timestamp index allowing you delete oldest entries quickly.

Timed map

data TimedMap t k a

A timed map is a regular map with timestamps and a timestamp index.

Constructors

TimedMap

Fields

tmMap :: Map k (a, t)

Underlying map with timestamps.

tmTimes :: Map t (Set k)

Timestamp index.

Instances

(Show t, Show k, Show a) => Show (TimedMap t k a)

Operations

Construct

tmEmpty :: TimedMap t k a

The empty timed map.

Read

tmFindWithDefault

Arguments

:: Ord k

=> a

Default, if key is not found.

-> k

Key to look up.

-> TimedMap t k a

Map to query.

-> a

Retrieved or default value.

Find a value with default.

tmLookup :: Ord k => k -> TimedMap t k a -> Maybe a

Look up the value for the given key.

Modify

tmInsert

Arguments

:: (Ord k, Ord t)

=> t

Timestamp.

-> k

Key.

-> a

Value.

-> TimedMap t k a

Original map.

-> TimedMap t k a

Map with the value added.

Insert a value into the map.

tmLimitAge :: (Ord t, Ord k) => t -> TimedMap t k a -> TimedMap t k a

Delete all items older than the specified timestamp.

tmLimitSize :: Ord k => Int -> TimedMap t k a -> TimedMap t k a

Delete at least as many oldest items as necessary to limit the map's size to the given value. If you have multiple keys with the same timestamp, this function can delete more keys than necessary.