Data.Rsv.RMMap

See Data.Rsv for an overview of what "reservation" data structures are.

This module implements a multi-map, where each insert is indexed by a key, and many independent inserts may be performed on the same key.

Documentation

data RMMap k a

empty :: RMMap k a

An empty RMMap.

Read operations

isEmpty :: RMMap k a -> Bool

(!) :: Ord k => RMMap k a -> k -> [a]

Write operations

insert :: Ord k => k -> a -> RMMap k a -> (Delete k a, RMMap k a)

Add an item to the list, returning a handle to remove it with. The same item may be added twice, in which case it will occupy multiple positions in the map, and the handles distinguish these occurences.

type Delete k a = RMMap k a -> (Maybe a, RMMap k a)

A map-transition that removes and retrieves the earlier-added item. If the item was already removed, Nothing is returned instead.

deleteKey :: Ord k => k -> RMMap k a -> RMMap k a

Write operations in StateT

sInsert :: (Ord k, Monad m) => k -> a -> StateT (RMMap k a) m (SDelete k a m)

Same as insert except in the StateT monad

type SDelete k a m = StateT (RMMap k a) m (Maybe a)

Same as Delete except in the StateT monad

sDeleteKey :: (Ord k, Monad m) => k -> StateT (RMMap k a) m ()

Same as deleteKey except in the StateT monad