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thoughts on Haskell and other software concerns
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reserving the name
wow i would actually really like to switch from GitHub Pages for my programming stuff, but Substack doesn’t let you use markdown? absolutely not
what about embedding a gist:
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{-# language OverloadedStrings, NumericUnderscores, ImportQualifiedPost #-} | |
module Lib where | |
import Data.Typeable | |
import Control.Monad | |
import Prelude hiding (log) | |
import Data.Text (Text) | |
import Data.Text qualified as Text | |
import Say | |
import UnliftIO.Concurrent | |
import UnliftIO.Exception | |
import System.Posix.Process | |
import System.Posix.Signals qualified as Posix (Handler (Catch), installHandler, sigTERM) | |
import System.Exit (ExitCode(..)) | |
log :: Text -> IO () | |
log msg = do | |
tid <- myThreadId | |
say $ mconcat | |
[ "[", Text.pack $ show tid, "]\t\t" | |
, msg | |
] | |
tshow :: Show a => a -> Text | |
tshow = Text.pack . show | |
someFunc :: IO () | |
someFunc = do | |
log "Starting App" | |
mainThread <- myThreadId | |
void (Posix.installHandler Posix.sigTERM (Posix.Catch (shutdown mainThread)) Nothing) | |
procId <- getProcessID | |
log $ mconcat ["ProcessID: ", tshow procId] | |
forkFinally (do | |
tid <- myThreadId | |
void (Posix.installHandler Posix.sigTERM (Posix.Catch (shutdown tid)) Nothing) | |
forever loop | |
) $ \eerr -> | |
case eerr of | |
Left (SomeException err) -> do | |
log $ mconcat ["Received exception: ", tshow err] | |
log $ mconcat ["Exception type: ", tshow (typeOf err)] | |
Right () -> | |
log "Exited successfully" | |
forever loop `finally` log "Exiting with Finally" | |
where | |
loop = do | |
threadDelay 1_000_000 | |
log "Waiting . . ." | |
shutdown tid = do | |
log "Shutting down gracefully" | |
throwTo tid ExitSuccess |
ah well the unicode character thing is really unfortunate
main :: IO ()
main = do
putStrLn "really, no syntax highlighting?? really???"