haskeline-0.6.3: A command-line interface for user input, written in Haskell.



This module provides a low-level API to the line history stored in the InputT monad transformer.

For most application, it should suffice to instead use the following Settings flags:

  • autoAddHistory: add nonblank lines to the command history (True by default).
  • historyFile: read/write the history to a file before and after the line input session.

If you do want custom history behavior, you may need to disable the above default setting(s).



data History Source


Show History 
Monad m => MonadState History (InputT m) 
Monad m => MonadState History (InputT m) 

addHistoryUnlessConsecutiveDupe :: String -> History -> HistorySource

Add a line to the history unless it matches the previously recorded line.

addHistoryRemovingAllDupes :: String -> History -> HistorySource

Add a line to the history, and remove all previous entries which are the same as it.

historyLines :: History -> [String]Source

The input lines stored in the history (newest first)

readHistory :: FilePath -> IO HistorySource

Reads the line input history from the given file. Returns emptyHistory if the file does not exist or could not be read.

writeHistory :: FilePath -> History -> IO ()Source

Writes the line history to the given file. If there is an error when writing the file, it will be ignored.

stifleHistory :: Maybe Int -> History -> HistorySource

Limit the number of lines stored in the history.

stifleAmount :: History -> Maybe IntSource

The maximum number of lines stored in the history. If Nothing, the history storage is unlimited.