v4.0.0-rc.1
Pre-release
Pre-release
This pre-release for version v4.0.0 features a revamped API for writing more expressive asynchronous programs with stronger guarantees.
Fiber
cooperative multi-tasking primitive for fork/join workflows- Stronger cleanup guarantees with
bracket
andsupervise
. - Reformulated
AVar
semantics
Migration Notes
- The low-level callback representation is no longer relevant. If you've defined
Aff
effects via the FFI, you should transition to usingControl.Monad.Eff.Compat
, which provides anEffFn
adapter. - The
AVar
API methods have changed to match Haskell'sMVar
API.putVar
effects now block until matched with atakeVar
. It's possible to recover similar behavior as the old API withforkAff (try (putVar avar value))
. - Several unlawful instances where removed for
Aff
(Alternative
,MonadPlus
, andMonadZero
).