{-# LANGUAGE TemplateHaskell #-}
module SimpleOptions
( module SimpleOptions
, module Options.Applicative
) where
import Control.Monad.Trans.Writer
import Data.Monoid ((<>))
import Data.Version (showVersion)
import Development.GitRev (gitDirty, gitHash)
import Language.Haskell.TH.Syntax (lift)
import Options.Applicative
simpleVersion version =
[|concat
[ "Version "
, $(lift $ showVersion version)
, ", Git revision "
, $gitHash
, if $gitDirty then " (dirty)" else ""
]
|]
simpleOptions :: String -- ^ version string
-> String -- ^ header
-> String -- ^ program description
-> Parser a -- ^ global settings
-> Writer (Mod CommandFields b) () -- ^ commands (use 'addCommand')
-> IO (a, b)
simpleOptions versionString h pd globalParser commandParser =
execParser $ info (helpOption <*> versionOption <*> config) desc
where
desc = fullDesc <> header h <> progDesc pd
helpOption =
abortOption ShowHelpText $
long "help" <>
help "Show this help text"
versionOption =
infoOption
versionString
(long "version" <>
help "Show version")
config = (,) <$> globalParser <*> subparser (execWriter commandParser)
addCommand :: String -- ^ command string
-> String -- ^ title of command
-> (a -> b) -- ^ constructor to wrap up command in common data type
-> Parser a -- ^ command parser
-> Writer (Mod CommandFields b) ()
addCommand cmd title constr inner = tell $ command
cmd
(info (constr <$> inner) (progDesc title))