pvar

Interface for a mutable veriable PVar that can hold values that have Prim instance.

Status

Language	Travis	Azure	Coveralls

Package	Hackage	Nightly	LTS
pvar

Overview

Main features include:

• Perfomance. There is practically no overhead when compared to operating on pure values, wlthough there is a higher memory overhead, since PVar is backed by a MutableByteArray#
• Atomic operations for PVars with Int values. This includes a unique atomicModifyIntPVar :: PrimMonad m => PVar (PrimState m) Int -> (Int -> (Int, a)) -> m a function that is not availiable in ghc-prim out of the box.
• Works in PrimMonad, therfore usable with ST, IO and various transformer monads.
• Easy access to PVar contents with Storable