compiler/Build/Interface.hs · elk

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elk/compiler/Build/Interface.hs

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1{-# OPTIONS_GHC -W #-}

2module Build.Interface (load,isValid) where

4import qualified Data.ByteString.Lazy as L

5import qualified Data.Binary as Binary

7import qualified Build.Print as Print

8import qualified Elm.Internal.Version as Version

9import System.Directory (doesFileExist)

10import AST.Module as Module

12load :: Binary.Binary a => FilePath -> IO a

13load filePath =

14 do exists <- doesFileExist filePath

15 case exists of

16 False -> Print.failure $ "Unable to find file " ++ filePath ++ " for deserialization!"

17 True -> do

18 bytes <- L.readFile filePath

19 case Binary.decodeOrFail bytes of

20 Right (_, _, binaryInfo) -> return binaryInfo

21 Left (_, offset, err) -> Print.failure $ msg offset err

23 where

24 msg offset err = concat

25 [ "Error reading build artifact: ", filePath, "\n"

26 , " '", err, "' at offset ", show offset, "\n"

27 , " The file was generated by a previous build and may be outdated or corrupt.\n"

28 , " Please remove the file and try again."

29 ]

31isValid :: FilePath -> (String, Module.Interface) -> Either String (String, Module.Interface)

32isValid filePath (name, interface) =

33 let version = iVersion interface in

34 if version == Version.elmVersion

35 then Right (name, interface)

36 else Left $ concat

37 [ "Error reading build artifact: ", filePath, "\n"

38 , " It was generated by version ", show version, " of the compiler,\n"

39 , " but you are using version ", show Version.elmVersion, "\n"

40 , " Please remove the file and try again.\n"

41 ]