| Portability | non-portable (requires libreadline) | 
|---|---|
| Stability | provisional | 
| Maintainer | libraries@haskell.org | 
System.Console.Readline
Description
A Haskell binding to the GNU readline library. The GNU Readline library provides a set of functions for use by applications that allow users to edit command lines as they are typed in. By default, the line editing commands are similar to those of emacs. A vi-style line editing interface is also available.
An example of a typical use of readline with history functionality is illustrated in the following read, eval, print loop:
 readEvalPrintLoop :: IO ()
 readEvalPrintLoop = do
   maybeLine <- readline "% "
   case maybeLine of 
    Nothing     -> return () -- EOF / control-d
    Just "exit" -> return ()
    Just line -> do addHistory line
                    putStrLn $ "The user input: " ++ (show line)
                    readEvalPrintLoop
- readline :: String -> IO (Maybe String)
- addHistory :: String -> IO ()
- getLineBuffer :: IO String
- setLineBuffer :: String -> IO ()
- getPoint :: IO Int
- setPoint :: Int -> IO ()
- getEnd :: IO Int
- setEnd :: Int -> IO ()
- getMark :: IO Int
- setMark :: Int -> IO ()
- setDone :: Bool -> IO ()
- setPendingInput :: Char -> IO ()
- setEraseEmptyLine :: Bool -> IO ()
- getPrompt :: IO String
- setAlreadyPrompted :: Bool -> IO ()
- getLibraryVersion :: IO String
- getTerminalName :: IO String
- setReadlineName :: String -> IO ()
- getInStream :: IO Handle
- getOutStream :: IO Handle
- setStartupHook :: Maybe (IO ()) -> IO ()
- setPreInputHook :: Maybe (IO ()) -> IO ()
- setEventHook :: Maybe (IO ()) -> IO ()
- setRedisplayFunction :: Maybe (IO ()) -> IO ()
- data Keymap
- newBareKeymap :: IO Keymap
- copyKeymap :: Keymap -> IO Keymap
- newKeymap :: IO Keymap
- freeKeymap :: Keymap -> IO ()
- getKeymap :: IO Keymap
- setKeymap :: Keymap -> IO ()
- getKeymapByName :: String -> IO Keymap
- getKeymapName :: Keymap -> IO (Maybe String)
- getExecutingKeymap :: IO Keymap
- getBindingKeymap :: IO Keymap
- type Callback = Int -> Char -> IO Int
- addDefun :: String -> Callback -> Maybe Char -> IO ()
- bindKey :: Char -> Callback -> IO ()
- bindKeyInMap :: Char -> Callback -> Keymap -> IO ()
- unbindKey :: Char -> IO ()
- unbindKeyInMap :: Char -> Keymap -> IO ()
- unbindCommandInMap :: String -> Keymap -> IO ()
- data Entry
- genericBind :: String -> Entry -> Keymap -> IO ()
- parseAndBind :: String -> IO ()
- readInitFile :: String -> IO ()
- namedFunction :: String -> IO (Maybe Callback)
- functionOfKeyseq :: String -> Maybe Keymap -> IO Entry
- functionDumper :: Bool -> IO ()
- listFunmapNames :: IO ()
- funmapNames :: IO [String]
- beginUndoGroup :: IO ()
- endUndoGroup :: IO ()
- data  UndoCode - = UndoDelete
- | UndoInsert
- | UndoBegin
- | UndoEnd
 
- addUndo :: UndoCode -> Int -> Int -> String -> IO ()
- freeUndoList :: IO ()
- doUndo :: IO Bool
- modifying :: Int -> Int -> IO ()
- redisplay :: IO ()
- forcedUpdateDisplay :: IO ()
- onNewLine :: IO ()
- onNewLineWithPrompt :: IO ()
- resetLineState :: IO ()
- message :: String -> IO ()
- clearMessage :: IO ()
- savePrompt :: IO ()
- restorePrompt :: IO ()
- insertText :: String -> IO ()
- deleteText :: Int -> Int -> IO ()
- copyText :: Int -> Int -> IO String
- killText :: Int -> Int -> IO ()
- readKey :: IO Char
- stuffChar :: Char -> IO Bool
- initialize :: IO ()
- resetTerminal :: Maybe String -> IO ()
- ding :: IO Bool
- displayMatchList :: [String] -> IO ()
- callbackHandlerInstall :: String -> (String -> IO ()) -> IO (IO ())
- callbackReadChar :: IO ()
- setCatchSignals :: Bool -> IO ()
- getCatchSignals :: IO Bool
- setCatchSigwinch :: Bool -> IO ()
- getCatchSigwinch :: IO Bool
- cleanupAfterSignal :: IO ()
- freeLineState :: IO ()
- resetAfterSignal :: IO ()
- resizeTerminal :: IO ()
- setSignals :: IO ()
- clearSignals :: IO ()
- completeInternal :: Char -> IO ()
- complete :: Int -> Char -> IO Int
- possibleCompletions :: Int -> Char -> IO Int
- insertCompletions :: Int -> Char -> IO Int
- completionMatches :: String -> (String -> IO [String]) -> IO (Maybe (String, [String]))
- filenameCompletionFunction :: String -> IO [String]
- usernameCompletionFunction :: String -> IO [String]
- setCompletionEntryFunction :: Maybe (String -> IO [String]) -> IO ()
- setAttemptedCompletionFunction :: Maybe (String -> Int -> Int -> IO (Maybe (String, [String]))) -> IO ()
- setFilenameQuotingFunction :: Maybe (String -> Bool -> Ptr CChar -> IO String) -> IO ()
- quoteFilename :: String -> Bool -> Ptr CChar -> IO String
- setFilenameDequotingFunction :: Maybe (String -> Maybe Char -> IO String) -> IO ()
- setCharIsQuotedP :: Maybe (String -> Int -> IO Bool) -> IO ()
- getCompletionQueryItems :: IO Int
- setCompletionQueryItems :: Int -> IO ()
- getBasicWordBreakCharacters :: IO String
- setBasicWordBreakCharacters :: String -> IO ()
- getBasicQuoteCharacters :: IO String
- setBasicQuoteCharacters :: String -> IO ()
- getCompleterWordBreakCharacters :: IO String
- setCompleterWordBreakCharacters :: String -> IO ()
- getCompleterQuoteCharacters :: IO String
- setCompleterQuoteCharacters :: String -> IO ()
- getFilenameQuoteCharacters :: IO String
- setFilenameQuoteCharacters :: String -> IO ()
- getSpecialPrefixes :: IO String
- setSpecialPrefixes :: String -> IO ()
- getCompletionAppendCharacter :: IO (Maybe Char)
- setCompletionAppendCharacter :: Maybe Char -> IO ()
- setIgnoreCompletionDuplicates :: Bool -> IO ()
- getIgnoreCompletionDuplicates :: IO Bool
- setFilenameCompletionDesired :: Bool -> IO ()
- getFilenameCompletionDesired :: IO Bool
- setFilenameQuotingDesired :: Bool -> IO ()
- getFilenameQuotingDesired :: IO Bool
- setInhibitCompletion :: Bool -> IO ()
- getInhibitCompletion :: IO Bool
- setAttemptedCompletionOver :: Bool -> IO ()
- getAttemptedCompletionOver :: IO Bool
- setIgnoreSomeCompletionsFunction :: Maybe ([String] -> IO [String]) -> IO ()
- setDirectoryCompletionHook :: Maybe (String -> IO String) -> IO ()
- setCompletionDisplayMatchesHook :: Maybe ([String] -> IO ()) -> IO ()
Documentation
Arguments
| :: String | prompt | 
| -> IO (Maybe String) | returns the line the user input, or Nothing if EOF is encountered. | 
readline is similar to System.IO.getLine, but with rich edit
 functionality and history capability.  readline will read a line
 from the terminal and return it, using prompt as a prompt.  If
 prompt is the empty string, no prompt is issued.  The line returned
 has the final newline removed, so only the text of the line
 remains.  A blank line returns the empty string.  If EOF is
 encountered while reading a line, and the line is empty, Nothing is
 returned.  If an EOF is read with a non-empty line, it is treated
 as a newline.
addHistory :: String -> IO ()
Add this command to the history. This allows users to search backward through history with C-r and step through with up and down arrows, among other things.
setLineBuffer :: String -> IO ()
setPendingInput :: Char -> IO ()
setEraseEmptyLine :: Bool -> IO ()
setAlreadyPrompted :: Bool -> IO ()
setReadlineName :: String -> IO ()
getInStream :: IO Handle
getOutStream :: IO Handle
data Keymap
copyKeymap :: Keymap -> IO Keymap
freeKeymap :: Keymap -> IO ()
getKeymapByName :: String -> IO Keymap
getKeymapName :: Keymap -> IO (Maybe String)
unbindKeyInMap :: Char -> Keymap -> IO ()
unbindCommandInMap :: String -> Keymap -> IO ()
parseAndBind :: String -> IO ()
readInitFile :: String -> IO ()
namedFunction :: String -> IO (Maybe Callback)
functionDumper :: Bool -> IO ()
listFunmapNames :: IO ()
funmapNames :: IO [String]
beginUndoGroup :: IO ()
endUndoGroup :: IO ()
data UndoCode
Constructors
| UndoDelete | |
| UndoInsert | |
| UndoBegin | |
| UndoEnd | 
freeUndoList :: IO ()
resetLineState :: IO ()
clearMessage :: IO ()
savePrompt :: IO ()
restorePrompt :: IO ()
insertText :: String -> IO ()
deleteText :: Int -> Int -> IO ()
initialize :: IO ()
resetTerminal :: Maybe String -> IO ()
displayMatchList :: [String] -> IO ()
callbackReadChar :: IO ()
setCatchSignals :: Bool -> IO ()
setCatchSigwinch :: Bool -> IO ()
freeLineState :: IO ()
resetAfterSignal :: IO ()
resizeTerminal :: IO ()
setSignals :: IO ()
clearSignals :: IO ()
completeInternal :: Char -> IO ()
possibleCompletions :: Int -> Char -> IO Int
insertCompletions :: Int -> Char -> IO Int
filenameCompletionFunction :: String -> IO [String]
usernameCompletionFunction :: String -> IO [String]
setAttemptedCompletionFunction :: Maybe (String -> Int -> Int -> IO (Maybe (String, [String]))) -> IO ()
setCompletionQueryItems :: Int -> IO ()
setBasicQuoteCharacters :: String -> IO ()
setFilenameQuoteCharacters :: String -> IO ()
setSpecialPrefixes :: String -> IO ()
setFilenameCompletionDesired :: Bool -> IO ()
setFilenameQuotingDesired :: Bool -> IO ()
setInhibitCompletion :: Bool -> IO ()
setAttemptedCompletionOver :: Bool -> IO ()