simple-get-opt 0.4 → 0.5

raw patch · 2 files changed

+51/−26 lines, 2 files

Files

• simple-get-opt.cabal +1/−1
• src/SimpleGetOpt.hs +50/−25

@@ -1,5 +1,5 @@ name:                simple-get-opt-version:             0.4+version:             0.5 synopsis:            A simple library for processing command-line options. description:   A simple library for processing command-line options.

@@ -9,11 +9,8 @@ >   } > > options :: OptSpec Settings-> options = OptSpec->   { progDefaults = Settings { verbose = False->                             , inPar   = 1->                             , files   = []->                             }+> options = optSpec+>   { progDescription = [ "A useful utility." ] > >   , progOptions = >       [ Option ['v'] ["verbose"]@@ -32,17 +29,22 @@ >       [ ("FILES",   "The files that need processing.") ] > >   , progParams = \p s -> Right s { files = p : files s }+>+>   , progArgOrder = Permute >   }  Here is what the usage information looks like: -> *Main> dumpUsage options +> *Main> dumpUsage options+> A useful utility.+>  > Parameters: >   FILES    The files that need processing.->+>  > Flags: >   -v      --verbose  Display more information while working. >   -p NUM  --par=NUM  Process that many files at once.+ -}  module SimpleGetOpt@@ -55,6 +57,8 @@   , OptSetter   , ArgDescr(..)   , GetOptException(..)+  , GetOpt.ArgOrder(..)+  , optSpec    -- * Information and error reporting.   , dumpUsage@@ -77,22 +81,36 @@  -- | Specification of a collection of options, described by type @a@. data OptSpec a = OptSpec-  { progDefaults :: a-    -- ^ Default options.-    -- This is what is used if no other options are provided.+  { progDescription :: [String]+    -- ^ Free form lines to be shown with the generated help    , progOptions  :: [OptDescr a]     -- ^ A list of options and command-line flags.    , progParamDocs       :: [(String,String)]-    -- ^ Documentatio for the free-form parameters.+    -- ^ Documentation for the free-form parameters.    , progParams      :: String -> OptSetter a-    -- ^ Add a parameter that is not an option or a flag-    -- (i.e., this is just a free form command line parameter).+    -- ^ Used to add the parameters that are not an option or a flag+    -- (i.e., this is just a free form command line parameter)+    -- in left-to-right order. +  , progArgOrder :: !(GetOpt.ArgOrder (OptSetter a))+    -- ^ What to do with parameters   } +-- | A default empty specification.  The default argument order is 'Permute'.+optSpec :: OptSpec a+optSpec = OptSpec+  { progDescription = []+  , progOptions     = []+  , progParamDocs   = []+  , progParams      = \_ _ -> Left "Unexpected parameter"+  , progArgOrder    = GetOpt.Permute+  }+++ -- | Describe an option. data OptDescr a = Option   { optShortFlags  :: [Char]@@ -148,11 +166,11 @@ -- | Process the given command line options according to the given spec. -- The options will be permuted to get flags. -- Returns errors on the 'Left'.-getOptsFrom :: OptSpec a -> [String] -> Either GetOptException a-getOptsFrom os as =-  do let (funs,files,errs) = GetOpt.getOpt GetOpt.Permute (specToGetOpt os) as+getOptsFrom :: a -> OptSpec a -> [String] -> Either GetOptException a+getOptsFrom dflt os as =+  do let (funs,files,errs) = GetOpt.getOpt (progArgOrder os) (specToGetOpt os) as      unless (null errs) $ Left (GetOptException errs)-     let (a, errs1) = foldl addOpt (progDefaults os,[]) funs+     let (a, errs1) = foldl addOpt (dflt,[]) funs      unless (null errs1) $ Left (GetOptException errs1)      let (b, errs2) = foldl (addFile (progParams os)) (a,[]) files      unless (null errs2) $ Left (GetOptException errs2)@@ -163,19 +181,19 @@ -- | Get the command-line options and process them according to the given spec. -- The options will be permuted to get flags. -- Throws a 'GetOptException' if some problems are found.-getOptsX :: OptSpec a -> IO a-getOptsX os =+getOptsX :: a -> OptSpec a -> IO a+getOptsX dflt os =   do as <- getArgs-     case getOptsFrom os as of+     case getOptsFrom dflt os as of        Left e -> throwIO e        Right a -> pure a  -- | Get the command-line options and process them according to the given spec. -- The options will be permuted to get flags. -- On failure, print an error message on standard error and exit.-getOpts :: OptSpec a -> IO a-getOpts os =-  getOptsX os `catch` \(GetOptException errs) -> reportUsageError os errs+getOpts :: a -> OptSpec a -> IO a+getOpts dlft os =+  getOptsX dlft os `catch` \(GetOptException errs) -> reportUsageError os errs  -- | Print the given messages on 'stderr' and show the program's usage info, -- then exit.@@ -193,13 +211,20 @@  -- | A string descibing the options. usageString :: OptSpec a -> String-usageString os = GetOpt.usageInfo (params ++ "Flags:") (specToGetOpt os)+usageString os = GetOpt.usageInfo (desc ++ params ++ "Flags:") (specToGetOpt os)   where+  desc = case progDescription os of+           [] -> []+           xs -> unlines xs ++ "\n"+   params = case concatMap ppParam (progParamDocs os) of              "" -> ""              ps -> "Parameters:\n" ++ ps ++ "\n" -  ppParam (x,y) = "  " ++ x ++ "    " ++ y ++ "\n"+  ppParam (x,y) = "  " ++ padKey x ++ " " ++ y ++ "\n"++  keyWidth = maximum (0 : map (length . fst) (progParamDocs os))+  padKey k = k ++ replicate (keyWidth - length k) ' '  data GetOptException = GetOptException [String] deriving Show