BSD-3-Clause licensed by Sven Panne and Edward Kmett
Maintained by Sven Panne
This version can be pinned in stack with:StateVar-1.2.1@sha256:b8bea664120dc78f5c15d9b8c0947d51dbc58a0b63ee49971fa7caac9f3e0845,1642

Module documentation for 1.2.1

Depends on 3 packages(full list with versions):
Used by 9 packages in nightly-2021-07-23(full list with versions):

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  • Explicitly mark Data.StateVar as Safe (or Trustworthy for GHC before 7.10).


  • Added instances for ForeignPtr.

  • Relaxed upper version bound for stm.

  • Track recent move of Contravariant to base.

  • Corrected HasUpdate’s superclass constraint.

  • Removed a couple of redundant typeclass constraints.

  • Relaxed upper version bound for transformers.

  • Documentation changes only.

  • Melded the API of foreign-var 0.1 with the API of StateVar
  • Introduced HasUpdate, which permits a wider array of uses of these combinators, including usecases that must update atomically.
  • Switched to multi-parameter typeclasses. This permits Ptr a to be directly employed as an instance of HasGetter, HasUpdate, and HasSetter.

  • Infrastructure changes only.

  • Exposed GettableStateVar, SettableStateVar and StateVar constructors to make writing own instances possible.
  • Added Functor, Applicative and Monad instances for GettableStateVar.
  • Various infrastructure improvements.

  • Initial release.