-- Hoogle documentation, generated by Haddock -- See Hoogle, http://www.haskell.org/hoogle/ -- | Command line argument processing -- -- This library provides an easy way to define command line parsers. Most -- users will want to use the System.Console.CmdArgs.Implicit -- module, whose documentation contains an example. -- --
-- data Foo = Foo {foo :: Int, bar :: Int}
--
--
--
-- impure = capture $ Foo {foo = 12, bar = many [1 &= "inner", 2]} &= "top"
--
--
--
-- pure = capture_ $ record Foo{} [foo := 12, bar :=+ [atom 1 += "inner", atom 2]] += "top"
--
--
-- Both evaluate to:
--
-- -- Capture (Ann "top") (Ctor (Foo 12 1) [Value 12, Many [Ann "inner" (Value 1), Value 2]] --module System.Console.CmdArgs.Annotate -- | The result of capturing some annotations. data Capture ann -- | Many values collapsed (many or many_) Many :: [Capture ann] -> Capture ann -- | An annotation attached to a value (&= or +=) Ann :: ann -> (Capture ann) -> Capture ann -- | A value (just a value, or atom) Value :: Any -> Capture ann -- | A missing field (a RecConError exception, or missing from -- record) Missing :: Any -> Capture ann -- | A constructor (a constructor, or record) Ctor :: Any -> [Capture ann] -> Capture ann -- | Any value, with a Data dictionary. data Any Any :: a -> Any -- | Return the value inside a capture. fromCapture :: Capture ann -> Any -- | Remove all Missing values by using any previous instances as default -- values defaultMissing :: Capture ann -> Capture ann -- | Capture a value. Note that if the value is evaluated more than once -- the result may be different, i.e. -- --
-- capture x /= capture x --capture :: (Data val, Data ann) => val -> Capture ann -- | Collapse multiple values in to one. many :: Data val => [val] -> val -- | Add an annotation to a value. -- -- It is recommended that anyone making use of this function redefine it -- with a more restrictive type signature to control the type of the -- annotation (the second argument). Any redefinitions of this function -- should add an INLINE pragma, to reduce the chance of incorrect -- optimisations. (&=) :: (Data val, Data ann) => val -> ann -> val infixl 2 &= -- | Capture the annotations from an annotated value. capture_ :: Show a => Annotate a -> Capture a -- | Collapse many annotated values in to one. many_ :: [Annotate a] -> Annotate a -- | Add an annotation to a value. (+=) :: Annotate ann -> ann -> Annotate ann infixl 2 += -- | Lift a pure value to an annotation. atom :: Data val => val -> Annotate ann -- | Create a constructor/record. The first argument should be the type of -- field, the second should be a list of fields constructed originally -- defined by := or :=+. -- -- This operation is not type safe, and may raise an exception at runtime -- if any field has the wrong type or label. record :: Data a => a -> [Annotate ann] -> Annotate ann -- | This type represents an annotated value. The type of the underlying -- value is not specified. data Annotate ann -- | Construct a field, fieldname := value. (:=) :: (c -> f) -> f -> Annotate ann -- | Add annotations to a field. (:=+) :: (c -> f) -> [Annotate ann] -> Annotate ann instance GHC.Show.Show System.Console.CmdArgs.Annotate.ExceptionInt instance GHC.Show.Show ann => GHC.Show.Show (System.Console.CmdArgs.Annotate.Capture ann) instance GHC.Exception.Exception System.Console.CmdArgs.Annotate.ExceptionInt instance GHC.Base.Functor System.Console.CmdArgs.Annotate.Capture -- | This module provides default values for many types. To use the default -- value simply write def. module System.Console.CmdArgs.Default -- | Class for default values. class Default a -- | Provide a default value, such as (), False, -- 0, [], Nothing. def :: Default a => a instance System.Console.CmdArgs.Default.Default () instance System.Console.CmdArgs.Default.Default GHC.Types.Bool instance System.Console.CmdArgs.Default.Default GHC.Types.Int instance System.Console.CmdArgs.Default.Default GHC.Integer.Type.Integer instance System.Console.CmdArgs.Default.Default GHC.Types.Float instance System.Console.CmdArgs.Default.Default GHC.Types.Double instance System.Console.CmdArgs.Default.Default [a] instance System.Console.CmdArgs.Default.Default (GHC.Base.Maybe a) instance System.Console.CmdArgs.Default.Default GHC.Int.Int8 instance System.Console.CmdArgs.Default.Default GHC.Int.Int16 instance System.Console.CmdArgs.Default.Default GHC.Int.Int32 instance System.Console.CmdArgs.Default.Default GHC.Int.Int64 instance System.Console.CmdArgs.Default.Default GHC.Types.Word instance System.Console.CmdArgs.Default.Default GHC.Word.Word8 instance System.Console.CmdArgs.Default.Default GHC.Word.Word16 instance System.Console.CmdArgs.Default.Default GHC.Word.Word32 instance System.Console.CmdArgs.Default.Default GHC.Word.Word64 instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2) => System.Console.CmdArgs.Default.Default (a1, a2) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3) => System.Console.CmdArgs.Default.Default (a1, a2, a3) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3, System.Console.CmdArgs.Default.Default a4) => System.Console.CmdArgs.Default.Default (a1, a2, a3, a4) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3, System.Console.CmdArgs.Default.Default a4, System.Console.CmdArgs.Default.Default a5) => System.Console.CmdArgs.Default.Default (a1, a2, a3, a4, a5) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3, System.Console.CmdArgs.Default.Default a4, System.Console.CmdArgs.Default.Default a5, System.Console.CmdArgs.Default.Default a6) => System.Console.CmdArgs.Default.Default (a1, a2, a3, a4, a5, a6) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3, System.Console.CmdArgs.Default.Default a4, System.Console.CmdArgs.Default.Default a5, System.Console.CmdArgs.Default.Default a6, System.Console.CmdArgs.Default.Default a7) => System.Console.CmdArgs.Default.Default (a1, a2, a3, a4, a5, a6, a7) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3, System.Console.CmdArgs.Default.Default a4, System.Console.CmdArgs.Default.Default a5, System.Console.CmdArgs.Default.Default a6, System.Console.CmdArgs.Default.Default a7, System.Console.CmdArgs.Default.Default a8) => System.Console.CmdArgs.Default.Default (a1, a2, a3, a4, a5, a6, a7, a8) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3, System.Console.CmdArgs.Default.Default a4, System.Console.CmdArgs.Default.Default a5, System.Console.CmdArgs.Default.Default a6, System.Console.CmdArgs.Default.Default a7, System.Console.CmdArgs.Default.Default a8, System.Console.CmdArgs.Default.Default a9) => System.Console.CmdArgs.Default.Default (a1, a2, a3, a4, a5, a6, a7, a8, a9) instance (System.Console.CmdArgs.Default.Default a1, System.Console.CmdArgs.Default.Default a2, System.Console.CmdArgs.Default.Default a3, System.Console.CmdArgs.Default.Default a4, System.Console.CmdArgs.Default.Default a5, System.Console.CmdArgs.Default.Default a6, System.Console.CmdArgs.Default.Default a7, System.Console.CmdArgs.Default.Default a8, System.Console.CmdArgs.Default.Default a9, System.Console.CmdArgs.Default.Default a10) => System.Console.CmdArgs.Default.Default (a1, a2, a3, a4, a5, a6, a7, a8, a9, a10) -- | Module for implementing CmdArgs helpers. A CmdArgs helper is an -- external program, that helps a user construct the command line -- arguments. To use a helper set the environment variable -- $CMDARGS_HELPER (or -- $CMDARGS_HELPER_YOURPROGRAM) to one of: -- --
-- [Line "Cooking for hungry people." -- ,Line "Welcome to my cookery recipe program, I sure hope you enjoy using it!" -- ,Line "" -- ,Cols ["Omlette"," A tasty eggy treat."] -- ,Cols [" -m"," --mushrooms"," Some mushrooms, or in fact any other ingredients you have in the cupboards"] -- ,Cols [" -e"," --eggs", " But always you need eggs"] -- ,Line "" -- ,Cols ["Spagetti Bolognaise", " An Italian delight."] -- ,Cols [" -s"," --spagetti"," The first word in the name"] -- ,Cols [" -b"," --bolognaise"," The second word in the name"] -- ,Cols [" -d"," --dolmio"," The magic ingredient!"] -- ,Line "" -- ,Line " The author of this program explicitly disclaims any liability for poisoning people who get their recipes off the internet."] ---- -- With putStrLn (showText (Wrap 50) demo) gives: -- --
-- Cooking for hungry people. -- Welcome to my cookery recipe program, I sure hope -- you enjoy using it! -- -- Omlette A tasty eggy treat. -- -m --mushrooms Some mushrooms, or in fact -- any other ingredients you have -- in the cupboards -- -e --eggs But always you need eggs -- -- Spagetti Bolognaise An Italian delight. -- -s --spagetti The first word in the name -- -b --bolognaise The second word in the name -- -d --dolmio The magic ingredient! -- -- The author of this program explicitly -- disclaims any liability for poisoning people -- who get their recipes off the internet. --module System.Console.CmdArgs.Text -- | How to output the text. data TextFormat -- | Display as HTML. HTML :: TextFormat -- | Display as text wrapped at a certain width (see defaultWrap). Wrap :: Int -> TextFormat -- | Wrap with the default width of 80 characters. defaultWrap :: TextFormat -- | The data type representing some text, typically used as -- [Text]. The formatting is described by: -- --
-- arguments :: Mode [(String,String)]
-- arguments = mode "explicit" [] "Explicit sample program" (flagArg (upd "file") "FILE")
-- [flagOpt "world" ["hello","h"] (upd "world") "WHO" "World argument"
-- ,flagReq ["greeting","g"] (upd "greeting") "MSG" "Greeting to give"
-- ,flagHelpSimple (("help",""):)]
-- where upd msg x v = Right $ (msg,x):v
--
--
--
-- And this can be invoked by:
--
--
-- main = do
-- xs <- processArgs arguments
-- if ("help","") `elem` xs then
-- print $ helpText [] HelpFormatDefault arguments
-- else
-- print xs
--
--
--
-- Groups: The Group structure allows flags/modes to be
-- grouped for the purpose of displaying help. When processing command
-- lines, the group structure is ignored.
--
-- Modes: The Explicit module allows multiple mode programs by
-- placing additional modes in modeGroupModes. Every mode is
-- allowed sub-modes, and thus multiple levels of mode may be created.
-- Given a mode x with sub-modes xs, if the first
-- argument corresponds to the name of a sub-mode, then that sub-mode
-- will be applied. If not, then the arguments will be processed by mode
-- x. Consequently, if you wish to force the user to explicitly
-- enter a mode, simply give sub-modes, and leave modeArgs as
-- Nothing. Alternatively, if you want one sub-mode to be
-- selected by default, place all it's flags both in the sub-mode and the
-- outer mode.
--
-- Parsing rules: Command lines are parsed as per most GNU
-- programs. Short arguments single letter flags start with -,
-- longer flags start with --, and everything else is considered
-- an argument. Anything after -- alone is considered to be an
-- argument. For example:
--
-- -- -f --flag argument1 -- --argument2 ---- -- This command line passes one single letter flag (f), one -- longer flag (flag) and two arguments (argument1 and -- --argument2). module System.Console.CmdArgs.Explicit -- | Process a list of flags (usually obtained from -- getArgs/expandArgsAt) with a mode. Returns -- Left and an error message if the command line fails to parse, -- or Right and the associated value. process :: Mode a -> [String] -> Either String a -- | Process the flags obtained by getArgs and -- expandArgsAt with a mode. Displays an error and exits -- with failure if the command line fails to parse, or returns the -- associated value. Implemented in terms of process. This -- function makes use of the following environment variables: -- --
-- FlagReq FlagOpt FlagOptRare/FlagNone -- -xfoo -x=foo -x=foo -x -foo -- -x foo -x=foo -x foo -x foo -- -x=foo -x=foo -x=foo -x=foo -- --xx foo --xx=foo --xx foo --xx foo -- --xx=foo --xx=foo --xx=foo --xx=foo --data FlagInfo -- | Required argument FlagReq :: FlagInfo -- | Optional argument FlagOpt :: String -> FlagInfo -- | Optional argument that requires an = before the value FlagOptRare :: String -> FlagInfo -- | No argument FlagNone :: FlagInfo -- | Extract the value from inside a FlagOpt or FlagOptRare, -- or raises an error. fromFlagOpt :: FlagInfo -> String -- | A function to take a string, and a value, and either produce an error -- message (Left), or a modified value (Right). type Update a = String -> a -> Either String a -- | A flag, consisting of a list of flag names and other information. data Flag a Flag :: [Name] -> FlagInfo -> Update a -> FlagHelp -> Help -> Flag a -- | The names for the flag. [flagNames] :: Flag a -> [Name] -- | Information about a flag's arguments. [flagInfo] :: Flag a -> FlagInfo -- | The way of processing a flag. [flagValue] :: Flag a -> Update a -- | The type of data for the flag argument, i.e. FILE/DIR/EXT [flagType] :: Flag a -> FlagHelp -- | The help message associated with this flag. [flagHelp] :: Flag a -> Help -- | An unnamed argument. Anything not starting with - is -- considered an argument, apart from "-" which is considered to -- be the argument "-", and any arguments following -- "--". For example: -- --
-- programname arg1 -j - --foo arg3 -- -arg4 --arg5=1 arg6 ---- -- Would have the arguments: -- --
-- ["arg1","-","arg3","-arg4","--arg5=1","arg6"] --data Arg a Arg :: Update a -> FlagHelp -> Bool -> Arg a -- | A way of processing the argument. [argValue] :: Arg a -> Update a -- | The type of data for the argument, i.e. FILE/DIR/EXT [argType] :: Arg a -> FlagHelp -- | Is at least one of these arguments required, the command line will -- fail if none are set [argRequire] :: Arg a -> Bool -- | Check that a mode is well formed. checkMode :: Mode a -> Maybe String -- | Like functor, but where the the argument isn't just covariant. class Remap m -- | Convert between two values. remap :: Remap m => (a -> b) -> (b -> (a, a -> b)) -> m a -> m b -- | Restricted version of remap where the values are isomorphic. remap2 :: Remap m => (a -> b) -> (b -> a) -> m a -> m b -- | Version of remap for the Update type alias. remapUpdate :: (a -> b) -> (b -> (a, a -> b)) -> Update a -> Update b -- | Create an empty mode specifying only modeValue. All other -- fields will usually be populated using record updates. modeEmpty :: a -> Mode a -- | Create a mode with a name, an initial value, some help text, a way of -- processing arguments and a list of flags. mode :: Name -> a -> Help -> Arg a -> [Flag a] -> Mode a -- | Create a list of modes, with a program name, an initial value, some -- help text and the child modes. modes :: String -> a -> Help -> [Mode a] -> Mode a -- | Create a flag taking no argument value, with a list of flag names, an -- update function and some help text. flagNone :: [Name] -> (a -> a) -> Help -> Flag a -- | Create a flag taking an optional argument value, with an optional -- value, a list of flag names, an update function, the type of the -- argument and some help text. flagOpt :: String -> [Name] -> Update a -> FlagHelp -> Help -> Flag a -- | Create a flag taking a required argument value, with a list of flag -- names, an update function, the type of the argument and some help -- text. flagReq :: [Name] -> Update a -> FlagHelp -> Help -> Flag a -- | Create an argument flag, with an update function and the type of the -- argument. flagArg :: Update a -> FlagHelp -> Arg a -- | Create a boolean flag, with a list of flag names, an update function -- and some help text. flagBool :: [Name] -> (Bool -> a -> a) -> Help -> Flag a -- | Create a help flag triggered by -?/--help. flagHelpSimple :: (a -> a) -> Flag a -- | Create a help flag triggered by -?/--help. The user -- may optionally modify help by specifying the format, such as: -- --
-- --help=all - help for all modes -- --help=html - help in HTML format -- --help=100 - wrap the text at 100 characters -- --help=100,one - full text wrapped at 100 characters --flagHelpFormat :: (HelpFormat -> TextFormat -> a -> a) -> Flag a -- | Create a version flag triggered by -V/--version. flagVersion :: (a -> a) -> Flag a -- | Create a version flag triggered by --numeric-version. flagNumericVersion :: (a -> a) -> Flag a -- | Create verbosity flags triggered by -v/--verbose and -- -q/--quiet flagsVerbosity :: (Verbosity -> a -> a) -> [Flag a] -- | Specify the format to output the help. data HelpFormat -- | Equivalent to HelpFormatAll if there is not too much text, -- otherwise HelpFormatOne. HelpFormatDefault :: HelpFormat -- | Display only the first mode. HelpFormatOne :: HelpFormat -- | Display all modes. HelpFormatAll :: HelpFormat -- | Bash completion information HelpFormatBash :: HelpFormat -- | Z shell completion information HelpFormatZsh :: HelpFormat -- | Generate a help message from a mode. The first argument is a prefix, -- which is prepended when not using HelpFormatBash or -- HelpFormatZsh. helpText :: [String] -> HelpFormat -> Mode a -> [Text] -- | Expand @ directives in a list of arguments, usually obtained -- from getArgs. As an example, given the file test.txt -- with the lines hello and world: -- --
-- expandArgsAt ["@test.txt","!"] == ["hello","world","!"] ---- -- Any @ directives in the files will be recursively expanded -- (raising an error if there is infinite recursion). -- -- To supress @ expansion, pass any @ arguments after -- --. expandArgsAt :: [String] -> IO [String] -- | Given a string, split into the available arguments. The inverse of -- joinArgs. splitArgs :: String -> [String] -- | Given a sequence of arguments, join them together in a manner that -- could be used on the command line, giving preference to the Windows -- cmd shell quoting conventions. -- -- For an alternative version, intended for actual running the result in -- a shell, see "System.Process.showCommandForUser" joinArgs :: [String] -> String -- | How to complete a command line option. The Show instance is -- suitable for parsing from shell scripts. data Complete -- | Complete to a particular value CompleteValue :: String -> Complete -- | Complete to a prefix, and a file CompleteFile :: String -> FilePath -> Complete -- | Complete to a prefix, and a directory CompleteDir :: String -> FilePath -> Complete -- | Given a current state, return the set of commands you could type now, -- in preference order. complete :: Mode a -> [String] -> (Int, Int) -> [Complete] -- | This module provides simple command line argument processing. The main -- function of interest is cmdArgs. A simple example is: -- --
-- data Sample = Sample {hello :: String} deriving (Show, Data, Typeable)
--
--
--
-- sample = Sample{hello = def &= help "World argument" &= opt "world"}
-- &= summary "Sample v1"
--
--
-- -- main = print =<< cmdArgs sample ---- -- Attributes are used to control a number of behaviours: -- --
-- sample = cmdArgsMode $ Sample{hello = ... -- as before
--
--
-- -- main = print =<< cmdArgsRun sample ---- -- Even using this scheme, sometimes GHC's optimisations may share values -- who have the same annotation. To disable sharing you may need to -- specify {-# OPTIONS_GHC -fno-cse #-} in the module you define -- the flags. -- -- Pure annotations: Alternatively, you may use pure annotations, -- which are referentially transparent, but less type safe and more -- verbose. The initial example may be written as: -- -- sample = record Sample{} [hello := def += -- help "World argument" += opt "world"] -- += summary "Sample v1" -- --
-- main = print =<< (cmdArgs_ sample :: IO Sample) ---- -- All the examples are written using impure annotations. To convert to -- pure annotations follow the rules: -- --
-- Ctor {field1 = value1 &= ann1, field2 = value2} &= ann2 ==> record Ctor{} [field1 := value1 += ann1, field2 := value2] += ann2
-- Ctor (value1 &= ann1) value2 &= ann2 ==> record Ctor{} [atom value1 += ann1, atom value2] += ann2
-- modes [Ctor1{...}, Ctor2{...}] ==> modes_ [record Ctor1{} [...], record Ctor2{} [...]]
-- Ctor {field1 = enum [X &= ann, Y]} ==> record Ctor{} [enum_ field1 [atom X += ann, atom Y]]
--
--
-- If you are willing to use TemplateHaskell, you can write in the impure
-- syntax, but have your code automatically translated to the pure style.
-- For more details see System.Console.CmdArgs.Quote.
module System.Console.CmdArgs.Implicit
-- | Take impurely annotated records and run the corresponding command
-- line. Shortcut for cmdArgsRun . cmdArgsMode.
--
-- To use cmdArgs with custom command line arguments see
-- withArgs.
cmdArgs :: Data a => a -> IO a
-- | Take impurely annotated records and turn them in to a Mode
-- value, that can make use of the System.Console.CmdArgs.Explicit
-- functions (i.e. process).
--
-- Annotated records are impure, and will only contain annotations on
-- their first use. The result of this function is pure, and can be
-- reused.
cmdArgsMode :: Data a => a -> Mode (CmdArgs a)
-- | Run a Mode structure. This function reads the command line arguments
-- and then performs as follows:
--
--
-- {hello = def &= opt "foo"}
-- -h --hello[=VALUE] (default=foo)
--
--
-- Note that all flags in CmdArgs are optional, and if omitted will use
-- their default value. Those annotated with opt also allow the
-- flag to be present without an associated value. As an example:
--
--
-- {hello = "DEFAULT" &= opt "OPTIONAL"}
--
--
--
-- $ main
-- {hello = "DEFAULT"}
-- $ main --hello
-- {hello = "OPTIONAL"}
-- $ main --hello=VALUE
-- {hello = "VALUE"}
--
opt :: (Show a, Typeable a) => a -> Ann
-- | Flag: "For this flag, users need to give something of type ..."
--
-- The the type of a flag's value, usually upper case. Only used for the
-- help message. Commonly the type will be FILE (typFile)
-- or DIR (typDir).
--
--
-- {hello = def &= typ "MESSAGE"}
-- -h --hello=MESSAGE
--
typ :: String -> Ann
-- | Flag: "Users must give a file for this flag's value."
--
-- Alias for typ FILE.
typFile :: Ann
-- | Flag: "Users must give a directory for this flag's value."
--
-- Alias for typ DIR.
typDir :: Ann
-- | Flag/Mode: "The help message is ..."
--
-- Descriptive text used in the help output.
--
--
-- {hello = def &= help "Help message"}
-- -h --hello=VALUE Help message
--
help :: String -> Ann
-- | Flag: "Use this flag name for this field."
--
-- Add flags which trigger this option.
--
--
-- {hello = def &= name "foo"}
-- -h --hello --foo=VALUE
--
name :: String -> Ann
-- | Flag: "Put non-flag arguments here."
--
-- All argument flags not captured by argPos are returned by
-- args.
--
--
-- {hello = def &= args}
--
args :: Ann
-- | Flag: "Put the nth non-flag argument here."
--
-- This field should be used to store a particular argument position
-- (0-based).
--
--
-- {hello = def &= argPos 0}
--
argPos :: Int -> Ann
-- | Flag/Mode: "Give these flags/modes a group name in the help output."
--
-- This mode will be used for all following modes/flags, until the next
-- groupname.
--
--
-- {hello = def &= groupname "Welcomes"}
-- Welcomes
-- -h --hello=VALUE
--
groupname :: String -> Ann
-- | Mode: "A longer description of this mode is ..."
--
-- Suffix to be added to the help message.
--
--
-- Sample{..} &= details ["More details on the website www.example.org"]
--
details :: [String] -> Ann
-- | Modes: "My program name/version/copyright is ..."
--
-- One line summary of the entire program, the first line of
-- --help and the only line of --version. If the string
-- contains a version number component will also provide
-- --numeric-version.
--
--
-- Sample{..} &= summary "CmdArgs v0.0, (C) Neil Mitchell 1981"
--
summary :: String -> Ann
-- | Mode: "If the user doesn't give a mode, use this one."
--
-- This mode is the default. If no mode is specified and a mode has this
-- attribute then that mode is selected, otherwise an error is raised.
--
--
-- modes [Mode1{..}, Mode2{..} &= auto, Mode3{..}]
--
auto :: Ann
-- | Modes: "My program executable is named ..."
--
-- This is the name of the program executable. Only used in the help
-- message. Defaults to the type of the mode.
--
--
-- Sample{..} &= program "sample"
--
program :: String -> Ann
-- | Flag: "Don't guess any names for this field."
--
-- A field should not have any flag names guessed for it. All flag names
-- must be specified by flag.
--
--
-- {hello = def &= explicit &= name "foo"}
-- --foo=VALUE
--
explicit :: Ann
-- | Flag/Mode: "Ignore this field, don't let the user set it."
--
-- A mode or field is not dealt with by CmdArgs.
--
--
-- {hello = def, extra = def &= ignore}
-- --hello=VALUE
--
ignore :: Ann
-- | Modes: "My program needs verbosity flags."
--
-- Add --verbose and --quiet flags.
verbosity :: Ann
-- | Modes: "Customise the help argument."
--
-- Add extra options to a help argument, such as help,
-- name, ignore or explicit.
--
--
-- Sample{..} &= helpArg [explicit, name "h"]
--
helpArg :: [Ann] -> Ann
-- | Modes: "Customise the version argument."
--
-- Add extra options to a version argument, such as help,
-- name, ignore, summary or explicit.
--
--
-- Sample{..} &= versionArg [ignore]
--
versionArg :: [Ann] -> Ann
-- | Modes: "Customise the verbosity arguments."
--
-- Add extra options to a verbosity arguments (--verbose and
-- --quiet), such as help, name, ignore or
-- explicit. The verbose options come first, followed by the quiet
-- options.
--
--
-- Sample{..} &= verbosityArgs [ignore] [name "silent", explicit]
--
verbosityArgs :: [Ann] -> [Ann] -> Ann
-- | Program: "Turn off @ expansion."
--
-- Usually arguments starting with @ are treated as a file containing a
-- set of arguments. This annotation turns off that behaviour.
--
--
-- Sample{..} &= noAtExpand
--
noAtExpand :: Ann
-- | Add an annotation to a value. Note that if the value is evaluated more
-- than once the annotation will only be available the first time.
(&=) :: Data val => val -> Ann -> val
-- | Modes: "I want a program with multiple modes, like darcs or cabal."
--
-- Takes a list of modes, and creates a mode which includes them all. If
-- you want one of the modes to be chosen by default, see auto.
--
-- -- data Modes = Mode1 | Mode2 | Mode3 deriving Data -- cmdArgs $ modes [Mode1,Mode2,Mode3] --modes :: Data val => [val] -> val -- | Flag: "I want several different flags to set this one field to -- different values." -- -- This annotation takes a type which is an enumeration, and provides -- multiple separate flags to set the field to each value. The first -- element in the list is used as the value of the field. -- --
-- data State = On | Off deriving Data
-- data Mode = Mode {state :: State}
-- cmdArgs $ Mode {state = enum [On &= help "Turn on",Off &= help "Turn off"]}
-- --on Turn on
-- --off Turn off
--
--
-- This annotation can be used to allow multiple flags within a field:
--
--
-- data Mode = Mode {state :: [State]}
-- cmdArgs $ Mode {state = enum [[] &= ignore, [On] &= help "Turn on", [Off] &= help "Turn off"]}
--
--
-- Now --on --off would produce Mode [On,Off].
enum :: Data val => [val] -> val
-- | Add an annotation to a value.
(+=) :: Annotate ann -> ann -> Annotate ann
infixl 2 +=
-- | Create a constructor/record. The first argument should be the type of
-- field, the second should be a list of fields constructed originally
-- defined by := or :=+.
--
-- This operation is not type safe, and may raise an exception at runtime
-- if any field has the wrong type or label.
record :: Data a => a -> [Annotate ann] -> Annotate ann
-- | Lift a pure value to an annotation.
atom :: Data val => val -> Annotate ann
-- | This type represents an annotated value. The type of the underlying
-- value is not specified.
data Annotate ann
-- | Construct a field, fieldname := value.
(:=) :: (c -> f) -> f -> Annotate ann
-- | Like enum, but using the pure annotations.
enum_ :: (Data c, Data f) => (c -> f) -> [Annotate Ann] -> Annotate Ann
-- | Like modes, but using the pure annotations.
modes_ :: [Annotate Ann] -> Annotate Ann
-- | The general type of annotations that can be associated with a value.
data Ann
-- | A mode. Do not use the Mode constructor directly, instead use
-- mode to construct the Mode and then record updates. Each
-- mode has three main features:
--
-- -- data T a b = C1 a b | C2 deriving (Typeable, Data) ---- -- GHC will generate an instance that is equivalent to -- --
-- instance (Data a, Data b) => Data (T a b) where -- gfoldl k z (C1 a b) = z C1 `k` a `k` b -- gfoldl k z C2 = z C2 -- -- gunfold k z c = case constrIndex c of -- 1 -> k (k (z C1)) -- 2 -> z C2 -- -- toConstr (C1 _ _) = con_C1 -- toConstr C2 = con_C2 -- -- dataTypeOf _ = ty_T -- -- con_C1 = mkConstr ty_T "C1" [] Prefix -- con_C2 = mkConstr ty_T "C2" [] Prefix -- ty_T = mkDataType "Module.T" [con_C1, con_C2] ---- -- This is suitable for datatypes that are exported transparently. class Typeable * a => Data a -- | The class Typeable allows a concrete representation of a type -- to be calculated. class Typeable k (a :: k) -- | This module provides a quotation feature to let you write command line -- arguments in the impure style, but have them translated into the pure -- style, as per System.Console.CmdArgs.Implicit. An example: -- --
-- {-# LANGUAGE TemplateHaskell, DeriveDataTypeable, MagicHash #-}
-- import System.Console.CmdArgs.Implicit
-- import System.Console.CmdArgs.Quote
--
-- data Sample = Sample {hello :: String} deriving (Show, Data, Typeable)
--
-- $(cmdArgsQuote [d|
-- sample = Sample{hello = def &=# help "World argument" &=# opt "world"}
-- &=# summary "Sample v1"
--
-- run = cmdArgs# sample :: IO Sample
-- |])
--
-- main = print =<< run
--
--
-- Inside cmdArgsQuote you supply the command line parser using
-- attributes in the impure style. If you run with
-- -ddump-splices (to see the Template Haskell output), you
-- would see:
--
--
-- run = cmdArgs_
-- (record Sample{} [hello := def += help "World argument" += opt "world"]
-- += summary "Sample v1")
-- :: IO Sample
--
--
-- Stubs
--
-- To define the original parser you may use either the standard impure
-- annotations ('(&=)', modes), or the stub annotations
-- versions defined in this module ('(&=#)', modes). The stub
-- versions do not include a Data constraint, so can be used in
-- situations where the Data instance is not yet available - typically
-- when defining the parser in the same module as the data type on GHC
-- 7.2 and above. The stub versions should never be used outside
-- cmdArgsQuote and will always raise an error.
--
-- Explicit types
--
-- There will be a limited number of situations where an impure parser
-- will require additional types, typically on the result of
-- cmdArgs if the result is used without a fixed type - for
-- example if you show it. Most users will not need to add any
-- types. In some cases you may need to remove some explicit types, where
-- the intermediate type of the annotations has changed - but again, this
-- change should be rare.
--
-- Completeness
--
-- The translation is not complete, although works for all practical
-- instances I've tried. The translation works by first expanding out the
-- expression (inlining every function defined within the quote, inlining
-- let bindings), then performs the translation. This scheme leads to two
-- consequences: 1) Any expensive computation executed inside the
-- quotation to produce the command line flags may be duplicated (a very
-- unlikely scenario). 2) As I do not yet have expansion rules for all
-- possible expressions, the expansion (and subsequently the translation)
-- may fail. I am interested in any bug reports where the feature does
-- not work as intended.
module System.Console.CmdArgs.Quote
-- | Quotation function to turn an impure version of
-- System.Console.CmdArgs.Implicit into a pure one. For details
-- see System.Console.CmdArgs.Quote.
cmdArgsQuote :: Q [Dec] -> Q [Dec]
-- | Version of &= without a Data context, only to be
-- used within cmdArgsQuote.
(&=#) :: a -> Ann -> a
-- | Version of modes without a Data context, only to be used
-- within cmdArgsQuote.
modes# :: [a] -> a
-- | Version of cmdArgsMode without a Data context, only to
-- be used within cmdArgsQuote.
cmdArgsMode# :: a -> Mode (CmdArgs a)
-- | Version of cmdArgs without a Data context, only to be
-- used within cmdArgsQuote.
cmdArgs# :: a -> IO a
-- | Version of enum without a Data context, only to be used
-- within cmdArgsQuote.
enum# :: [a] -> a
-- | This module re-exports the implicit command line parser.
module System.Console.CmdArgs
-- | This provides a compatiblity wrapper to the
-- System.Console.GetOpt module in base. That module is
-- essentially a Haskell port of the GNU getopt library.
--
-- Changes: The changes from GetOpt are listed in the
-- documentation for each function.
module System.Console.CmdArgs.GetOpt
-- | Given a help text and a list of option descriptions, generate a
-- Mode.
convert :: String -> [OptDescr a] -> Mode ([a], [String])
-- | Process the command-line, and return the list of values that matched
-- (and those that didn't). The arguments are:
--
--