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{-# LANGUAGE CPP #-}
module Examples.Commands where
import Data.List
import Data.Monoid
import Options.Applicative
#if __GLASGOW_HASKELL__ <= 702
(<>) :: Monoid a => a -> a -> a
(<>) = mappend
#endif
data Sample
= Hello [String]
| Goodbye
deriving (Eq, Show)
hello :: Parser Sample
hello = Hello <$> many (argument str (metavar "TARGET..."))
sample :: Parser Sample
sample = subparser
( command "hello"
(info hello
(progDesc "Print greeting"))
<> command "goodbye"
(info (pure Goodbye)
(progDesc "Say goodbye"))
)
<|> subparser
( command "bonjour"
(info hello
(progDesc "Print greeting"))
<> command "au-revoir"
(info (pure Goodbye)
(progDesc "Say goodbye"))
<> commandGroup "French commands:"
<> hidden
)
run :: Sample -> IO ()
run (Hello targets) = putStrLn $ "Hello, " ++ intercalate ", " targets ++ "!"
run Goodbye = putStrLn "Goodbye."
opts :: ParserInfo Sample
opts = info (sample <**> helper) idm
main :: IO ()
main = execParser opts >>= run
|
