Re: [Haskell-cafe] multi-thread and lazy evaluation

The real question is, does this mean that GHC is stopping the world every time it puts an MVar? Tim ---------- Původní zpráva ---------- Od: Brandon Allbery Datum: 24. 12. 2012 Předmět: Re: [Haskell-cafe] multi-thread and lazy evaluation " On Mon, Dec 24, 2012 at 8:45 AM, Corentin Dupont wrote: " execBlocking :: MVar (Maybe MyData) -> IO () execBlocking mv = do    let (a::String) = a    --If you uncomment the next line, it will work    --putStrLn $ show a    putMVar mv (Just $ MyData a "toto") " It's laziness, yes; you need to do something along the lines of

let a = length a `seq` a

or possibly Control.Exception.evaluate(http://Control.Exception.evaluate) needs to be involved somewhere.   -- brandon s allbery kf8nh                               sine nomine associates allbery.b@gmail.com(mailto:allbery.b@gmail.com)                                  ballbery@sinenomine.net(mailto:ballbery@sinenomine.net) unix, openafs, kerberos, infrastructure, xmonad        http://sinenomine.net (http://sinenomine.net) "