package stt

Extending base's ST with IOArrays

The Control.Monad.STT.ST type is otherwise the same as base's Control.Monad.ST.ST, but rather than sequencing only operations on single-valued STRefs, package stt provides STTRef and STTArray for safe sequencing of conceptually-pure computations with IORef and IOArray.

The STT Monad Transformer

Since ST is a conceptually pure monad, we can extend other monads with mutable state just like we can with the traditional pure Control.Monad.State.StateT with the new interface Control.Monad.STT.MonadSTT and its canonical transformer Control.Monad.STT.STT.