vault-0.3.0.4: a persistent store for values of arbitrary types

Safe HaskellNone
LanguageHaskell98

Data.Vault.Lazy

Contents

Description

A persistent store for values of arbitrary types.

The Vault type in this module is strict in the keys but lazy in the values.

Synopsis

Vault

type Vault = Vault RealWorld Source

A persistent store for values of arbitrary types.

This variant is the simplest and creates keys in the IO monad. See the module Data.Vault.ST if you want to use it with the ST monad instead.

type Key = Key RealWorld Source

Keys for the vault.

empty :: Vault Source

The empty vault.

newKey :: IO (Key a) Source

Create a new key for use with a vault.

lookup :: Key a -> Vault -> Maybe a Source

Lookup the value of a key in the vault.

insert :: Key a -> a -> Vault -> Vault Source

Insert a value for a given key. Overwrites any previous value.

adjust :: (a -> a) -> Key a -> Vault -> Vault Source

Adjust the value for a given key if it's present in the vault.

delete :: Key a -> Vault -> Vault Source

Delete a key from the vault.

union :: Vault -> Vault -> Vault Source

Merge two vaults (left-biased).

Locker

type Locker = Locker RealWorld Source

A persistent store for a single value.

lock :: Key a -> a -> Locker Source

Put a single value into a Locker.

unlock :: Key a -> Locker -> Maybe a Source

Retrieve the value from the Locker.