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GHC 10.0.0.20260917 · lts/ghc-10.0.x · 8fef28d · 2026-11-02

Modulepolysemy-zoo-0.8.2.0Haskell2010

Polysemy.KVStore

Contents

Effect
Actions
Interpretations

Synopsis

data KVStore
value lookupKV
value lookupOrThrowKV
value existsKV
value writeKV
value deleteKV
value updateKV
value modifyKV
value runKVStoreAsState
value runKVStorePurely

Packagepolysemy-zoo-0.8.2.0
Exports10
LanguageHaskell2010
LicenceBSD-3-Clause
SourceKVStore.hs

Effect

datadata KVStore k1 v (m :: k) a where

Models things like Redis, HTTP GET/POST, etc. Things that are keyed, have a value, and may or may not be there.

Constructors

LookupKV :: k2 -> KVStore k1 v m (Maybe v)
UpdateKV :: k2 -> Maybe v -> KVStore k1 v m ()

Actions

valuelookupKV :: Member (KVStore k v) r => k -> Sem r (Maybe v)

valuelookupOrThrowKV

:: Members '[KVStore k v, Error e] r
=> k -> e
-> k
-> Sem r v

valueexistsKV :: Member (KVStore k v) r => k -> Sem r Bool

valuewriteKV :: Member (KVStore k v) r => k -> v -> Sem r ()

valuedeleteKV :: Member (KVStore k v) r => k -> Sem r ()

valueupdateKV :: Member (KVStore k v) r => k -> Maybe v -> Sem r ()

valuemodifyKV

:: Member (KVStore k v) r
=> v
Default value if the key isn't present
-> (v -> v)
-> k
-> Sem r ()

Interpretations

valuerunKVStoreAsState

:: Ord k
=> Sem (KVStore k v ': r) a
-> Sem (State (Map k v) ': r) a

valuerunKVStorePurely

:: Ord k
=> Map k v
-> Sem (KVStore k v ': r) a
-> Sem r (Map k v, a)