Distribution/Types/ExeDependency.hs

    {-# LANGUAGE DeriveDataTypeable #-}
    {-# LANGUAGE DeriveGeneric      #-}
    module Distribution.Types.ExeDependency
      ( ExeDependency(..)
      , qualifiedExeName
      ) where

    import Distribution.Compat.Prelude
    import Prelude ()

    import Distribution.Parsec.Class
    import Distribution.Pretty
    import Distribution.Text
    import Distribution.Types.ComponentName
    import Distribution.Types.PackageName
    import Distribution.Types.UnqualComponentName
    import Distribution.Version                   (VersionRange, anyVersion)

    import qualified Distribution.Compat.CharParsing as P
    import           Distribution.Compat.ReadP  ((<++))
    import qualified Distribution.Compat.ReadP  as Parse
    import           Text.PrettyPrint           (text, (<+>))

    -- | Describes a dependency on an executable from a package
    --
    data ExeDependency = ExeDependency
                         PackageName
                         UnqualComponentName -- name of executable component of package
                         VersionRange
                         deriving (Generic, Read, Show, Eq, Typeable, Data)

    instance Binary ExeDependency
    instance NFData ExeDependency where rnf = genericRnf

    instance Pretty ExeDependency where
      pretty (ExeDependency name exe ver) =
        (pretty name <<>> text ":" <<>> pretty exe) <+> pretty ver

    instance Parsec ExeDependency where
        parsec = do
            name <- lexemeParsec
            _    <- P.char ':'
            exe  <- lexemeParsec
            ver  <- parsec <|> pure anyVersion
            return (ExeDependency name exe ver)

    instance Text ExeDependency where
      parse = do name <- parse
                 _ <- Parse.char ':'
                 exe <- parse
                 Parse.skipSpaces
                 ver <- parse <++ return anyVersion
                 Parse.skipSpaces
                 return (ExeDependency name exe ver)

    qualifiedExeName :: ExeDependency -> ComponentName
    qualifiedExeName (ExeDependency _ ucn _) = CExeName ucn