{-# LANGUAGE
    DeriveDataTypeable
  , GeneralizedNewtypeDeriving
  , StandaloneDeriving
  , UnicodeSyntax
  #-}
module Data.URI.Internal.Scheme
    ( Scheme
    , unsafeCreateScheme
    )
    where
import Data.Ascii (CIAscii)
import Data.CaseInsensitive
import Data.Hashable
import Data.String
import Data.Typeable

-- |'Scheme' names consist of a non-empty sequence of characters
-- beginning with a letter and followed by any combination of letters,
-- digits, plus (\'+\'), period (\'.\'), or hyphen (\'-\'):
-- <http://tools.ietf.org/html/rfc3986#section-3.1>
newtype Scheme = Scheme CIAscii
    deriving ( Eq
             , FoldCase
             , Hashable
             , Ord
             , Show
             , Typeable
             )
-- scheme = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )

-- |'isString' is a fast but unsafe way to create 'Scheme' such that
-- no validation on the string is performed.
deriving instance IsString Scheme

-- |Converts a 'CIAscii' to 'Scheme' without any validation on the
-- string.
unsafeCreateScheme ∷ CIAscii → Scheme
{-# INLINE CONLIKE unsafeCreateScheme #-}
unsafeCreateScheme = Scheme