@@ -259,3 +259,49 @@ The advantages of this package are:
* Correct handling of asynchronous exceptions.
* GHC specific functionality like forkOn and forkIOWithUnmask.")
(license license:bsd-3)))
+
+(define-public ghc-concurrent-extra
+ (package
+ (name "ghc-concurrent-extra")
+ (version "0.7.0.12")
+ (source
+ (origin
+ (method url-fetch)
+ (uri (string-append
+ "https://hackage.haskell.org/package/concurrent-extra/concurrent-extra-"
+ version
+ ".tar.gz"))
+ (sha256
+ (base32
+ "1y8xk460fvnw0idzdiylmm874sjny4q9jxb1js9fjz8lw2wns3h4"))))
+ (build-system haskell-build-system)
+ (inputs
+ `(("ghc-unbounded-delays" ,ghc-unbounded-delays)))
+ (native-inputs
+ `(("ghc-hunit" ,ghc-hunit)
+ ("ghc-random" ,ghc-random)
+ ("ghc-test-framework" ,ghc-test-framework)
+ ("ghc-test-framework-hunit"
+ ,ghc-test-framework-hunit)
+ ("ghc-async" ,ghc-async)))
+ (home-page
+ "https://github.com/basvandijk/concurrent-extra")
+ (synopsis "Extra concurrency primitives")
+ (description
+ "The concurrent-extra package offers among other things the following
+selection of synchronisation primitives:
+* Broadcast: Wake multiple threads by broadcasting a value.
+* Event: Wake multiple threads by signalling an event.
+* Lock: Enforce exclusive access to a resource. Also known as a binary
+semaphore or mutex. The package additionally provides an alternative that
+works in the STM monad.
+* RLock: A lock which can be acquired multiple times by the same thread.
+Also known as a reentrant mutex.
+* ReadWriteLock: Multiple-reader, single-writer locks. Used to protect
+shared resources which may be concurrently read, but only sequentially
+written.
+* ReadWriteVar: Concurrent read, sequential write variables.
+Please consult the API documentation of the individual modules for more
+detailed information.
+This package was inspired by the concurrency libraries of Java and Python.")
+ (license license:bsd-3)))