d7583f3 · typeable/pandoc

git.iko.soy/typeable/pandoc

Error: change type of handleError.

It now lives in IO and gives a proper message + exit instead of calling 'error'. We shouldn't be making it easier for people to raise error on pure code. And this is better for the main application in IO.

commitd7583f365951373158a55ce344ba6b345ea481ec authorJohn MacFarlane <jgm@berkeley.edu> dateSat 3 Dec 2016, 22:35 (10 years ago) parent1a0d93a

3 files changed+15−16

compare with master

unifiedsplit

src/Text/Pandoc.hs+3−4 src/Text/Pandoc/Class.hs+1−1 src/Text/Pandoc/Error.hs+11−11

src/Text/Pandoc.hs+3−4

@@ -38,12 +38,11 @@ inline links:

3838> module Main where

3939> import Text.Pandoc

4040>

41−> markdownToRST :: String -> String

41+> markdownToRST :: String -> Either PandocError String

4242> markdownToRST =

43−> writeRST def {writerReferenceLinks = True} .

44−> handleError . readMarkdown def

43+> writeRST def {writerReferenceLinks = True} . readMarkdown def

4544>

46−> main = getContents >>= putStrLn . markdownToRST

45+> main = getContents >>= either error return markdownToRST >>= putStrLn

4746

4847Note: all of the readers assume that the input text has @'\n'@

4948line endings. So if you get your input text from a web form,

src/Text/Pandoc/Class.hs+1−1

@@ -190,7 +190,7 @@ withWarningsToStderr f = do

190190 return x

191191

192192runIOorExplode :: PandocIO a -> IO a

193−runIOorExplode ma = handleError <$> runIO ma

193+runIOorExplode ma = runIO ma >>= handleError

194194

195195newtype PandocIO a = PandocIO {

196196 unPandocIO :: ExceptT PandocError (StateT CommonState IO) a

src/Text/Pandoc/Error.hs+11−11

@@ -35,6 +35,7 @@ import Text.Parsec.Error

3535import Text.Parsec.Pos hiding (Line)

3636import Data.Generics (Typeable)

3737import Control.Exception (Exception)

38+import Text.Pandoc.Shared (err)

3839

3940type Input = String

4041

@@ -54,15 +55,15 @@ data PandocError = PandocFileReadError FilePath

5455

5556instance Exception PandocError

5657

57−-- | An unsafe method to handle `PandocError`s.

58−handleError :: Either PandocError a -> a

59−handleError (Right r) = r

60−handleError (Left err) =

61− case err of

62− PandocFileReadError fp -> error $ "problem reading " ++ fp

63− PandocShouldNeverHappenError s -> error s

64− PandocSomeError s -> error s

65− PandocParseError s -> error s

58+-- | Handle PandocError by exiting with an error message.

59+handleError :: Either PandocError a -> IO a

60+handleError (Right r) = return r

61+handleError (Left e) =

62+ case e of

63+ PandocFileReadError fp -> err 61 $ "problem reading " ++ fp

64+ PandocShouldNeverHappenError s -> err 62 s

65+ PandocSomeError s -> err 63 s

66+ PandocParseError s -> err 64 s

6667 PandocParsecError input err' ->

6768 let errPos = errorPos err'

6869 errLine = sourceLine errPos

@@ -73,6 +74,5 @@ handleError (Left err) =

7374 ,"\n", replicate (errColumn - 1) ' '

7475 ,"^"]

7576 else ""

76− in error $ "\nError at " ++ show err'

77− ++ errorInFile

77+ in err 65 $ "\nError at " ++ show err' ++ errorInFile

7878