vault-0.3.0.2: a persistent store for values of arbitrary types

Safe HaskellNone

Data.Vault.ST.Lazy

Contents

Description

A persistent store for values of arbitrary types. Variant for the ST monad.

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

Synopsis

Vault

data Vault s Source

Instances

data Key s a Source

empty :: Vault sSource

The empty vault.

newKey :: ST s (Key s a)Source

Create a new key for use with a vault.

lookup :: Key s a -> Vault s -> Maybe aSource

Lookup the value of a key in the vault.

insert :: Key s a -> a -> Vault s -> Vault sSource

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

adjust :: (a -> a) -> Key s a -> Vault s -> Vault sSource

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

delete :: Key s a -> Vault s -> Vault sSource

Delete a key from the vault.

union :: Vault s -> Vault s -> Vault sSource

Merge two vaults (left-biased).

Locker

data Locker s Source

lock :: Key s a -> a -> Locker sSource

Put a single value into a Locker.

unlock :: Key s a -> Locker s -> Maybe aSource

Retrieve the value from the Locker.