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.Compiler.Version as Compiler

9import System.Directory (doesFileExist)

10import AST.Module as Module

13load :: Binary.Binary a => FilePath -> IO a

14load filePath =

15 do exists <- doesFileExist filePath

16 case exists of

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

18 True -> do

19 bytes <- L.readFile filePath

20 case Binary.decodeOrFail bytes of

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

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

24 where

25 msg offset err = concat

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

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

28 , " The file was generated by a previous build and may be outdated or corrupt.\n"

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

30 ]

33isValid :: FilePath -> (String, Module.Interface) -> Either String (String, Module.Interface)

34isValid filePath (name, interface) =

35 let version = iVersion interface in

36 if version == Compiler.version

37 then Right (name, interface)

38 else Left $ concat

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

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

41 , " but you are using version ", Compiler.version, "\n"

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

43 ]