Ormolu

A formatter for Haskell source code.

Documentation

ormolu

Arguments

:: MonadIO m

=> Config RegionIndices

Ormolu configuration

-> FilePath

Location of source file

-> String

Input to format

-> m Text

Format a String, return formatted version as Text.

The function

• Takes String because that's what GHC parser accepts.
• Needs IO because some functions from GHC that are necessary to setup parsing context require IO. There should be no visible side-effects though.
• Takes file name just to use it in parse error messages.
• Throws OrmoluException.

ormoluFile

Arguments

:: MonadIO m

=> Config RegionIndices

Ormolu configuration

-> FilePath

Location of source file

-> m Text

Resulting rendition

Load a file and format it. The file stays intact and the rendered version is returned as Text.

ormoluFile cfg path =
  liftIO (readFile path) >>= ormolu cfg path

ormoluStdin

Arguments

:: MonadIO m

=> Config RegionIndices

Ormolu configuration

-> m Text

Resulting rendition

Read input from stdin and format it.

ormoluStdin cfg =
  liftIO (hGetContents stdin) >>= ormolu cfg "<stdin>"

data Config region

Ormolu configuration.

Constructors

Config

Fields

• cfgDynOptions :: ![DynOption]

  Dynamic options to pass to GHC parser

• cfgUnsafe :: !Bool

  Do formatting faster but without automatic detection of defects

• cfgDebug :: !Bool

  Output information useful for debugging

• cfgCheckIdempotence :: !Bool

  Checks if re-formatting the result is idempotent

• cfgColorMode :: !ColorMode

  Whether to use colors and other features of ANSI terminals

• cfgRegion :: !region

  Region selection

Instances

Functor Config

Defined in Ormolu.Config

Methods

fmap :: (a -> b) -> Config a -> Config b

(<$) :: a -> Config b -> Config a

Eq region => Eq (Config region)

Defined in Ormolu.Config

Methods

(==) :: Config region -> Config region -> Bool

(/=) :: Config region -> Config region -> Bool

Show region => Show (Config region)

Defined in Ormolu.Config

Methods

showsPrec :: Int -> Config region -> ShowS

show :: Config region -> String

showList :: [Config region] -> ShowS

data ColorMode

Whether to use colors and other features of ANSI terminals.

Constructors

Never

Always

Auto

Instances

Eq ColorMode

Defined in Ormolu.Terminal

Methods

(==) :: ColorMode -> ColorMode -> Bool

(/=) :: ColorMode -> ColorMode -> Bool

Show ColorMode

Defined in Ormolu.Terminal

Methods

showsPrec :: Int -> ColorMode -> ShowS

show :: ColorMode -> String

showList :: [ColorMode] -> ShowS

data RegionIndices

Region selection as the combination of start and end line numbers.

Constructors

RegionIndices

Fields

• regionStartLine :: !(Maybe Int)

  Start line of the region to format

• regionEndLine :: !(Maybe Int)

  End line of the region to format

Instances

Eq RegionIndices

Defined in Ormolu.Config

Methods

(==) :: RegionIndices -> RegionIndices -> Bool

(/=) :: RegionIndices -> RegionIndices -> Bool

Show RegionIndices

Defined in Ormolu.Config

Methods

showsPrec :: Int -> RegionIndices -> ShowS

show :: RegionIndices -> String

showList :: [RegionIndices] -> ShowS

defaultConfig :: Config RegionIndices

Default Config RegionIndices.

newtype DynOption

A wrapper for dynamic options.

Constructors

DynOption

Fields

• unDynOption :: String

Instances

Eq DynOption

Defined in Ormolu.Config

Methods

(==) :: DynOption -> DynOption -> Bool

(/=) :: DynOption -> DynOption -> Bool

Ord DynOption

Defined in Ormolu.Config

Methods

compare :: DynOption -> DynOption -> Ordering

(<) :: DynOption -> DynOption -> Bool

(<=) :: DynOption -> DynOption -> Bool

(>) :: DynOption -> DynOption -> Bool

(>=) :: DynOption -> DynOption -> Bool

max :: DynOption -> DynOption -> DynOption

min :: DynOption -> DynOption -> DynOption

Show DynOption

Defined in Ormolu.Config

Methods

showsPrec :: Int -> DynOption -> ShowS

show :: DynOption -> String

showList :: [DynOption] -> ShowS

data OrmoluException

Ormolu exception representing all cases when Ormolu can fail.

Constructors

OrmoluParsingFailed SrcSpan String

Parsing of original source code failed

OrmoluOutputParsingFailed SrcSpan String

Parsing of formatted source code failed

OrmoluASTDiffers FilePath [SrcSpan]

Original and resulting ASTs differ

OrmoluNonIdempotentOutput TextDiff

Formatted source code is not idempotent

OrmoluUnrecognizedOpts (NonEmpty String)

Some GHC options were not recognized

OrmoluCabalFileParsingFailed FilePath

Cabal file parsing failed

OrmoluMissingStdinInputFile

Missing input file path when using stdin input and accounting for .cabal files

Instances

Eq OrmoluException

Defined in Ormolu.Exception

Methods

(==) :: OrmoluException -> OrmoluException -> Bool

(/=) :: OrmoluException -> OrmoluException -> Bool

Show OrmoluException

Defined in Ormolu.Exception

Methods

showsPrec :: Int -> OrmoluException -> ShowS

show :: OrmoluException -> String

showList :: [OrmoluException] -> ShowS

Exception OrmoluException

Defined in Ormolu.Exception

Methods

toException :: OrmoluException -> SomeException

fromException :: SomeException -> Maybe OrmoluException

displayException :: OrmoluException -> String

withPrettyOrmoluExceptions

Arguments

:: ColorMode

Color mode

-> IO ExitCode

Action that may throw an exception

-> IO ExitCode

Inside this wrapper OrmoluException will be caught and displayed nicely.