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{-# LANGUAGE LambdaCase #-}
module Main
( main
) where
import Control.Exception ( Exception (..), SomeException )
import System.Exit ( ExitCode (..) )
import Web.Browser ( openBrowser, openBrowserWithExitCode )
main :: IO ()
main = do
openBrowser "https://haskell.org/" >>= \case
True -> putStrLn "The operation succeeded!"
False -> putStrLn "The operation failed!"
blankLine
putStrLn "Help with debugging:"
putStrLn "Try a good URL:"
tryOpenGoodUrl >>= reportResult
blankLine
putStrLn "Try a bad URL:"
tryOpenBadUrl >>= reportResult
where
tryOpenGoodUrl :: IO (Either SomeException (ExitCode, String, String))
tryOpenGoodUrl = openBrowserWithExitCode "https://haskell.org/"
tryOpenBadUrl :: IO (Either SomeException (ExitCode, String, String))
tryOpenBadUrl = openBrowserWithExitCode "example-bad-url"
reportResult = \case
Left e -> putStrLn $ "Exception: " <> displayException e
Right (ec, out, err) -> do
putStrLn $ "Exit code: " <> show ec
putStrLn $ "Standard output: " <> out
putStrLn $ "Standard error: " <> err
blankLine = putStrLn ""
|
