Options.Harg.Types

Documentation

type OptReader a = String -> Either String a

data Opt a

The basic option type

Constructors

Opt

Fields

• _optLong :: Maybe String

  Modifier for long options (e.g. --user)

• _optShort :: Maybe Char

  Modifier for short options (e.g. -u)

• _optHelp :: Maybe String

  Option help to be shown when invoked with --help/-h or in case of error

• _optMetavar :: Maybe String

  Metavar to be shown in the help description

• _optEnvVar :: Maybe String

  Environment variable for use with EnvSource

• _optDefault :: Maybe a

  Default value

• _optReader :: OptReader a

  Option parser

• _optType :: OptType a

  Option type

Instances

Functor Opt

Defined in Options.Harg.Types

Methods

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

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

data OptType a

Option types

Constructors

OptionOptType

FlagOptType a

a is the active value for the flag parser

ArgumentOptType

Instances

Functor OptType

Defined in Options.Harg.Types

Methods

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

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

data OptAttr

Constructors

OptDefault

OptOptional

Intermediate option types

data OptionOpt (attr :: [OptAttr]) a

Option for flags with arguments. Corresponds to option.

Constructors

OptionOpt

Fields

• _oLong :: Maybe String
• _oShort :: Maybe Char
• _oHelp :: Maybe String
• _oMetavar :: Maybe String
• _oEnvVar :: Maybe String
• _oDefault :: Maybe a
• _oReader :: OptReader a

Instances

IsOpt OptionOpt attr

Defined in Options.Harg.Construct

Methods

toOpt :: OptionOpt attr a -> Opt a

HasOptional OptionOpt a

Defined in Options.Harg.Construct

Methods

optOptional :: NotInAttrs OptDefault a "optOptional" "optDefault" => OptionOpt a a0 -> OptionOpt (OptOptional ': a) (Maybe a0)

HasDefault OptionOpt a

Defined in Options.Harg.Construct

Methods

optDefault :: NotInAttrs OptOptional a "optDefault" "optOptional" => a0 -> OptionOpt a a0 -> OptionOpt (OptDefault ': a) a0

HasEnvVar OptionOpt a

Defined in Options.Harg.Construct

Methods

optEnvVar :: String -> OptionOpt a a0 -> OptionOpt a a0

HasMetavar OptionOpt a

Defined in Options.Harg.Construct

Methods

optMetavar :: String -> OptionOpt a a0 -> OptionOpt a a0

HasHelp OptionOpt a

Defined in Options.Harg.Construct

Methods

optHelp :: String -> OptionOpt a a0 -> OptionOpt a a0

HasShort OptionOpt a

Defined in Options.Harg.Construct

Methods

optShort :: Char -> OptionOpt a a0 -> OptionOpt a a0

HasLong OptionOpt a

Defined in Options.Harg.Construct

Methods

optLong :: String -> OptionOpt a a0 -> OptionOpt a a0

data FlagOpt (attr :: [OptAttr]) a

Option for flags that act like switches between a default and an active value. Corresponds to flag.

Constructors

FlagOpt

Fields

• _fLong :: Maybe String
• _fShort :: Maybe Char
• _fHelp :: Maybe String
• _fEnvVar :: Maybe String
• _fDefault :: a
• _fReader :: OptReader a
• _fActive :: a

Instances

IsOpt FlagOpt attr

Defined in Options.Harg.Construct

Methods

toOpt :: FlagOpt attr a -> Opt a

HasEnvVar FlagOpt a

Defined in Options.Harg.Construct

Methods

optEnvVar :: String -> FlagOpt a a0 -> FlagOpt a a0

HasHelp FlagOpt a

Defined in Options.Harg.Construct

Methods

optHelp :: String -> FlagOpt a a0 -> FlagOpt a a0

HasShort FlagOpt a

Defined in Options.Harg.Construct

Methods

optShort :: Char -> FlagOpt a a0 -> FlagOpt a a0

HasLong FlagOpt a

Defined in Options.Harg.Construct

Methods

optLong :: String -> FlagOpt a a0 -> FlagOpt a a0

data ArgumentOpt (attr :: [OptAttr]) a

Option for arguments (no long/short specifiers). Corresponds to argument.

Constructors

ArgumentOpt

Fields

• _aHelp :: Maybe String
• _aMetavar :: Maybe String
• _aEnvVar :: Maybe String
• _aDefault :: Maybe a
• _aReader :: OptReader a

Instances

IsOpt ArgumentOpt attr

Defined in Options.Harg.Construct

Methods

toOpt :: ArgumentOpt attr a -> Opt a

HasOptional ArgumentOpt a

Defined in Options.Harg.Construct

Methods

optOptional :: NotInAttrs OptDefault a "optOptional" "optDefault" => ArgumentOpt a a0 -> ArgumentOpt (OptOptional ': a) (Maybe a0)

HasDefault ArgumentOpt a

Defined in Options.Harg.Construct

Methods

optDefault :: NotInAttrs OptOptional a "optDefault" "optOptional" => a0 -> ArgumentOpt a a0 -> ArgumentOpt (OptDefault ': a) a0

HasEnvVar ArgumentOpt a

Defined in Options.Harg.Construct

Methods

optEnvVar :: String -> ArgumentOpt a a0 -> ArgumentOpt a a0

HasMetavar ArgumentOpt a

Defined in Options.Harg.Construct

Methods

optMetavar :: String -> ArgumentOpt a a0 -> ArgumentOpt a a0

HasHelp ArgumentOpt a

Defined in Options.Harg.Construct

Methods

optHelp :: String -> ArgumentOpt a a0 -> ArgumentOpt a a0

data OptError

Datatype that holds errors that arise when running the sources. The reason why this is the only place where errors occur is that, if something goes wrong when running the parser, it will be handled by optparse-applicative.

Constructors

OptError

Fields

• _oeOpt :: SomeOpt

  Existentially quantified Opt

• _oeSource :: Maybe String

  Source name

• _oeDesc :: String

  Error description

data SomeOpt where

Existential wrapper for Opt, so that many options can be carried in a list.

Constructors

SomeOpt :: Opt a -> SomeOpt

type Environment = [(String, String)]

Environment variable pairs, can be retrieved with getEnvironment.

type Args = [String]

Command line arguments, can be retrieved with getArgs.

data HargCtx

Context to carry around, that contains environment variables and command line arguments.

Constructors

HargCtx

Fields

• _hcEnv :: Environment
• _hcArgs :: Args

getCtx :: IO HargCtx

ctxFromArgs :: Args -> IO HargCtx

ctxFromEnv :: Environment -> IO HargCtx

pureCtx :: Environment -> Args -> HargCtx

toOptError :: Opt a -> Maybe String -> String -> OptError