#14810: Define MVar "This function is atomic only if there are no other producers for this MVar." -------------------------------------+------------------------------------- Reporter: akfp | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: libraries/base | Version: 8.2.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Documentation | Unknown/Multiple bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by osa1): Agreed that the documentation should be improved. I was also confused about this some time ago. Producer simply means "putMVar". For example, `swapMVar` takes the current value and puts a new value. If another thread puts between the `swapMVar`s take and put, `swapMVar` blocks and other threads observe the intermediate step, so it won't be atomic in this case. Similarly consumer means "takeMVar". Would you like to open a pull request? I think we accept documentation patches via Github PRs these days. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14810#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler