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What about Go or Node make it more designed around concurrency than Haskell? It sounds like you are trying to say Erlang, Go, and Node have "first class concurr

What about Go or Node make it more designed around concurrency than Haskell? It sounds like you are trying to say Erlang, Go, and Node have "first class concurrency". I'd agree that Erlang does, but I'd say that Node and Go do not. I'm almost tempted to wager the same is true for Lisp, but don't have enough experience with concurrency in Lisp. Furthermore I'd wager that Go and Node have nothing in the realm of concurrency that Haskell doesn't have. If I'm wrong, I look forward to finding out ;)

sanderjd 12y ago
"Languages aren't defined by what they make possible, but by what they make easy", to which I would add "and idiomatic". Go and Node make their (very different) concurrency features easy and idiomatic. Maybe Haskell does too, though, and I just don't know it well enough!
- codygman 12y ago
  Here's 2 Examples (Warning: Didn't run them and could have missed imports). One parallelizing a sudoku solver and the other making a reminder program concurrent. Both are from Parallel and Concurrent Programming In Haskell[0]. Sequential version[1]: import Sudoku import Control.Exception import System.Environment import Data.Maybe main :: IO () main = do [f] <- getArgs file <- readFile f let puzzles = lines file solutions = map solve puzzles print (length (filter isJust solutions)) Parallel version[2]: import Sudoku import Control.Exception import System.Environment import Data.Maybe import Control.Parallel.Strategies (parMap) -- line that changed main :: IO () main = do [f] <- getArgs file <- readFile f let puzzles = lines file solutions = runEval (parMap solve puzzles) -- line that changed print (length (filter isJust solutions)) Here's an example making a small reminder program concurrent: Sequential[3]: import Control.Concurrent import Text.Printf import Control.Monad main = forever $ do s <- getLine forkIO $ setReminder s setReminder :: String -> IO () setReminder s = do let t = read s :: Int printf "Ok, I'll remind you in %d seconds\n" t threadDelay (10^6 * t) printf "%d seconds is up! BING!\BEL\n" t Concurrent[4]: import Control.Concurrent import Text.Printf import Control.Monad main = loop where loop = do s <- getLine if s == "exit" then return () else do forkIO $ setReminder s loop setReminder :: String -> IO () setReminder s = do let t = read s :: Int printf "Ok, I'll remind you in %d seconds\n" t threadDelay (10^6 * t) printf "%d seconds is up! BING!\BEL\n" t 0: http://chimera.labs.oreilly.com/books/1230000000929/index.html http://chimera.labs.oreilly.com/books/1230000000929/index.ht... 1: http://chimera.labs.oreilly.com/books/1230000000929/ch02.html#import_sudoku_i http://chimera.labs.oreilly.com/books/1230000000929/ch02.htm... 2: http://chimera.labs.oreilly.com/books/1230000000929/ch02.html#par-eval_00000169 http://chimera.labs.oreilly.com/books/1230000000929/ch02.htm... 3: http://chimera.labs.oreilly.com/books/1230000000929/ch07.html#import_control_id3 http://chimera.labs.oreilly.com/books/1230000000929/ch07.htm... 4: http://chimera.labs.oreilly.com/books/1230000000929/ch07.html#sec_reminders http://chimera.labs.oreilly.com/books/1230000000929/ch07.htm...
  - sanderjd 12y ago
    Thanks!

sanderjd 12y ago

"Languages aren't defined by what they make possible, but by what they make easy", to which I would add "and idiomatic". Go and Node make their (very different) concurrency features easy and idiomatic. Maybe Haskell does too, though, and I just don't know it well enough!

codygman 12y ago
Here's 2 Examples (Warning: Didn't run them and could have missed imports). One parallelizing a sudoku solver and the other making a reminder program concurrent. Both are from Parallel and Concurrent Programming In Haskell[0]. Sequential version[1]: import Sudoku import Control.Exception import System.Environment import Data.Maybe main :: IO () main = do [f] <- getArgs file <- readFile f let puzzles = lines file solutions = map solve puzzles print (length (filter isJust solutions)) Parallel version[2]: import Sudoku import Control.Exception import System.Environment import Data.Maybe import Control.Parallel.Strategies (parMap) -- line that changed main :: IO () main = do [f] <- getArgs file <- readFile f let puzzles = lines file solutions = runEval (parMap solve puzzles) -- line that changed print (length (filter isJust solutions)) Here's an example making a small reminder program concurrent: Sequential[3]: import Control.Concurrent import Text.Printf import Control.Monad main = forever $ do s <- getLine forkIO $ setReminder s setReminder :: String -> IO () setReminder s = do let t = read s :: Int printf "Ok, I'll remind you in %d seconds\n" t threadDelay (10^6 * t) printf "%d seconds is up! BING!\BEL\n" t Concurrent[4]: import Control.Concurrent import Text.Printf import Control.Monad main = loop where loop = do s <- getLine if s == "exit" then return () else do forkIO $ setReminder s loop setReminder :: String -> IO () setReminder s = do let t = read s :: Int printf "Ok, I'll remind you in %d seconds\n" t threadDelay (10^6 * t) printf "%d seconds is up! BING!\BEL\n" t 0: http://chimera.labs.oreilly.com/books/1230000000929/index.html http://chimera.labs.oreilly.com/books/1230000000929/index.ht... 1: http://chimera.labs.oreilly.com/books/1230000000929/ch02.html#import_sudoku_i http://chimera.labs.oreilly.com/books/1230000000929/ch02.htm... 2: http://chimera.labs.oreilly.com/books/1230000000929/ch02.html#par-eval_00000169 http://chimera.labs.oreilly.com/books/1230000000929/ch02.htm... 3: http://chimera.labs.oreilly.com/books/1230000000929/ch07.html#import_control_id3 http://chimera.labs.oreilly.com/books/1230000000929/ch07.htm... 4: http://chimera.labs.oreilly.com/books/1230000000929/ch07.html#sec_reminders http://chimera.labs.oreilly.com/books/1230000000929/ch07.htm...
- sanderjd 12y ago
  Thanks!