Data.Rsv.RList

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

This module implements a list, where each insert is appended to its tail.

Documentation

data RList a

empty :: RList a

An empty RList.

Read operations

isEmpty :: RList a -> Bool

toList :: RList a -> [a]

Write operations

insert :: a -> RList a -> (Delete a, RList a)

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

type Delete a = RList a -> (Maybe a, RList a)

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

Write operations in StateT

sInsert :: Monad m => a -> StateT (RList a) m (SDelete a m)

Same as insert except in the StateT monad

type SDelete a m = StateT (RList a) m (Maybe a)

Same as Delete except in the StateT monad