    {-# LANGUAGE OverloadedStrings #-}

    --------------------------------------------------------------------------------
    --  See end of this file for licence information.
    --------------------------------------------------------------------------------
    -- |
    --  Module      :  MapDecimal
    --  Copyright   :  (c) 2003, Graham Klyne, 2009 Vasili I Galchin,
    --                     2011 William Waites, 2011, 2012 Douglas Burke
    --  License     :  GPL V2
    --
    --  Maintainer  :  Douglas Burke
    --  Stability   :  experimental
    --  Portability :  OverloadedStrings
    --
    --  This module defines the datatytpe mapping and relation values
    --  used for RDF dataype @xsd:decimal@.
    --
    --------------------------------------------------------------------------------

    module Swish.RDF.Datatype.XSD.MapDecimal (mapXsdDecimal) where

    import Swish.Datatype (DatatypeMap(..))

    import qualified Data.Text as T
    import qualified Data.Text.Read as T

    ------------------------------------------------------------
    --  Implementation of DatatypeMap for xsd:decimal
    ------------------------------------------------------------

    -- | Functions that perform lexical-to-value
    --  and value-to-canonical-lexical mappings for @xsd:decimal@ values.
    --
    mapXsdDecimal :: DatatypeMap Double
    mapXsdDecimal :: DatatypeMap Double
    mapXsdDecimal = DatatypeMap :: forall vt.
    (Text -> Maybe vt) -> (vt -> Maybe Text) -> DatatypeMap vt
    DatatypeMap
        { -- mapL2V :: T.Text -> Maybe Double
          mapL2V :: Text -> Maybe Double
    mapL2V = \txt :: Text
    txt -> case Reader Double
    T.double Text
    txt of
                             Right (val :: Double
    val, "") -> Double -> Maybe Double
    forall a. a -> Maybe a
    Just Double
    val
                             _ -> Maybe Double
    forall a. Maybe a
    Nothing

          -- mapV2L :: Double -> Maybe T.Text
          -- TODO: for now convert via String as issues with text-format
          --       (inability to use with ghci)
        , mapV2L :: Double -> Maybe Text
    mapV2L = Text -> Maybe Text
    forall a. a -> Maybe a
    Just (Text -> Maybe Text) -> (Double -> Text) -> Double -> Maybe Text
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . String -> Text
    T.pack (String -> Text) -> (Double -> String) -> Double -> Text
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Double -> String
    forall a. Show a => a -> String
    show
        }

    --------------------------------------------------------------------------------
    --
    --  Copyright (c) 2003, Graham Klyne, 2009 Vasili I Galchin,
    --                2011 William Waites, 2011, 2012 Douglas Burke
    --
    --  All rights reserved.
    --
    --  This file is part of Swish.
    --
    --  Swish is free software; you can redistribute it and/or modify
    --  it under the terms of the GNU General Public License as published by
    --  the Free Software Foundation; either version 2 of the License, or
    --  (at your option) any later version.
    --
    --  Swish is distributed in the hope that it will be useful,
    --  but WITHOUT ANY WARRANTY; without even the implied warranty of
    --  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    --  GNU General Public License for more details.
    --
    --  You should have received a copy of the GNU General Public License
    --  along with Swish; if not, write to:
    --    The Free Software Foundation, Inc.,
    --    59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    --
    --------------------------------------------------------------------------------