atomic-primops-0.8.7: A safe approach to CAS and other atomic ops in Haskell.

After GHC 7.4 a new `casMutVar#` primop became available, but it's difficult to use safely, because pointer equality is a highly unstable property in Haskell. This library provides a safer method based on the concept of Tickets. . Also, this library uses the "foreign primop" capability of GHC to add access to other variants that may be of interest, specifically, compare and swap inside an array. . Note that as of GHC 7.8, the relevant primops have been included in GHC itself. This library is engineered to work pre- and post-GHC-7.8, while exposing the same interface.