cli/Hcompta/CLI/Args.hs

   1 {-# LANGUAGE TupleSections #-}
   2 module Hcompta.CLI.Args where
   3
   4 import           System.Console.GetOpt
   5                  ( getOpt
   6                  , ArgOrder(..)
   7                  , OptDescr(..)
   8                  )
   9
  10 import           Hcompta.CLI.Context (Context)
  11 import qualified Hcompta.CLI.Write as Write
  12
  13 type Options context
  14  = [OptDescr (Context -> context -> IO context)]
  15
  16 parse
  17  :: Context
  18  -> (IO String)
  19  -> Options context
  20  ->    (context, [String])
  21  -> IO (context, [String])
  22 parse context usage options (ctx, args) =
  23         case getOpt RequireOrder options args of
  24          (parsers, cmds, []) -> do
  25                 foldl (\acc parser -> acc >>= parser context) (return ctx) parsers
  26                 >>= return . (, cmds)
  27          (_, _, errs) -> do
  28                 usage >>= Write.fatal context . (concat errs ++)