content: {-
      Copyright 2015 Markus Ongyerth, Stephan Guenther
  
      This file is part of Monky.
  
      Monky is free software: you can redistribute it and/or modify
      it under the terms of the GNU Lesser General Public License as published by
      the Free Software Foundation, either version 3 of the License, or
      (at your option) any later version.
  
      Monky 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 Lesser General Public License for more details.
  
      You should have received a copy of the GNU Lesser General Public License
      along with Monky.  If not, see <http://www.gnu.org/licenses/>.
  -}
  {-# LANGUAGE CPP #-}
  {-|
  Module      : Monky.VersionTH
  Description : The TemplateHaskell splice required by Monky.Version
  Maintainer  : ongy
  Stability   : testing
  Portability : Linux
  
  -}
  module Monky.VersionTH
  where
  
  import Data.List (isPrefixOf)
  import Language.Haskell.TH
  import Monky.Utility
  
  #if MIN_VERSION_base(4,8,0)
  #else
  import Control.Applicative ((<$>))
  #endif
  
  -- |Get the version string from monky.cabal and convert it to a 4tupel
  versionTH :: Q Exp
  versionTH = do
    content <- lines <$> runIO (readFile "monky.cabal")
    let parts = map read $ splitAtEvery "." $ getVersionString content
    pure . TupE $ map (Just . LitE . IntegerL) parts
    where getVLine = head . filter ("version:" `isPrefixOf`)
          getVersionString = flip (!!) 1 . words . getVLine
  