Changed readDataFile to look first in user data directory.

This way all of the pandoc data files can be overridden by
user files.

git-svn-id: https://pandoc.googlecode.com/svn/trunk@1693 788f1e2b-df1e-0410-8736-df70ead52e1b

src/Text/Pandoc/Shared.hs

@@ -118,13 +118,13 @@ import Data.Char ( toLower, toUpper, ord, isLower, isUpper, isAlpha,
 import Data.List ( find, isPrefixOf, intercalate )
 import Network.URI ( parseURI, URI (..), isAllowedInURI )
 import System.Directory
+import System.FilePath ( FilePath, (</>) )
 import Prelude hiding ( putStrLn, writeFile, readFile, getContents )
 import System.IO.UTF8
 import Data.Generics
 import qualified Control.Monad.State as S
 import Control.Monad (join)
 import Paths_pandoc (getDataFileName)
-
 --
 -- List processing
 --
@@ -1033,6 +1033,9 @@ inDirectory path action = do
   setCurrentDirectory oldDir
   return result
 
--- | Read file from the Cabal data directory.
+-- | Read file from user data directory or, if not found there, from
+-- Cabal data directory.  On unix the user data directory is @$HOME/.pandoc@.
 readDataFile :: FilePath -> IO String
-readDataFile fname = getDataFileName fname >>= readFile
+readDataFile fname = do
+  userDir <- getAppUserDataDirectory "pandoc"
+  catch (readFile $ userDir </> fname) (\_ -> getDataFileName fname >>= readFile) 

src/Text/Pandoc/Templates.hs

@@ -49,11 +49,7 @@ import Text.ParserCombinators.Parsec
 import Control.Monad (liftM)
 import qualified Control.Exception as E (try, IOException)
 import System.FilePath
-import System.Directory
-import Prelude hiding (readFile)
-import System.IO.UTF8 (readFile)
 import Text.Pandoc.Shared (readDataFile)
-import Paths_pandoc
 
 -- | Get the default template, either from the application's user data
 -- directory (~/.pandoc on unix) or from the cabal data directory.
@@ -62,21 +58,8 @@ getDefaultTemplate "native" = return $ Right ""
 getDefaultTemplate "odt" = getDefaultTemplate "opendocument"
 getDefaultTemplate format = do
   let format' = takeWhile (/='+') format  -- strip off "+lhs" if present
-  ut <- getTemplateFromUserDataDirectory format'
-  case ut of
-       Right t -> return $ Right t
-       Left _  -> getTemplateFromCabalDataDirectory format'
+  E.try $ readDataFile $ "templates" </> format' <.> "template"
  
-getTemplateFromUserDataDirectory :: String -> IO (Either E.IOException String)
-getTemplateFromUserDataDirectory format = E.try $ do
-  userDir <- getAppUserDataDirectory "pandoc"
-  let templatePath = userDir </> "templates" </> format <.> "template"
-  readFile templatePath
-
-getTemplateFromCabalDataDirectory :: String -> IO (Either E.IOException String)
-getTemplateFromCabalDataDirectory format = E.try $
-  readDataFile $ "templates" </> format <.> "template"
-
 -- | Renders a template 
 renderTemplate :: [(String,String)]  -- ^ Assoc. list of values for variables
                -> String             -- ^ Template