Documentation

Fields

• terminalID :: String

  Text identifier for the output device. Used for debugging.

• releaseTerminal :: IO ()

  Release the terminal just prior to application exit and reset it to its state prior to application startup.

• reserveDisplay :: IO ()

  Clear the display and initialize the terminal to some initial display state.

  The expectation of a program is that the display starts in some The initial state. initial state would consist of fixed values:

  • cursor at top left
  • UTF-8 character encoding
  • drawing characteristics are the default
• releaseDisplay :: IO ()

  Return the display to the state before reserveDisplay If no previous state then set the display state to the initial state.

• setDisplayBounds :: (Int, Int) -> IO ()

  Sets the current display bounds (width, height).

• displayBounds :: IO DisplayRegion

  Returns the current display bounds.

• outputByteBuffer :: ByteString -> IO ()

  Output the bytestring to the terminal device.

• supportsCursorVisibility :: Bool

  Specifies whether the cursor can be shown / hidden.

• supportsMode :: Mode -> Bool

  Indicates support for terminal modes for this output device.

• setMode :: Mode -> Bool -> IO ()

  Enables or disables a mode (does nothing if the mode is unsupported).

• getModeStatus :: Mode -> IO Bool

  Returns whether a mode is enabled.

• assumedStateRef :: IORef AssumedState
   
• mkDisplayContext :: Output -> DisplayRegion -> IO DisplayContext

  Acquire display access to the given region of the display. Currently all regions have the upper left corner of (0,0) and the lower right corner at (max displayWidth providedWidth, max displayHeight providedHeight)

• ringTerminalBell :: IO ()

  Ring the terminal bell if supported.

• supportsBell :: IO Bool

  Returns whether the terminal has an audio bell feature.

• supportsItalics :: IO Bool

  Returns whether the terminal supports italicized text.

  This is terminal-dependent and should make a best effort to determine whether this feature is supported, but even if the terminal advertises support (e.g. via terminfo) that might not be a reliable indicator of whether the feature will work as desired.

• supportsStrikethrough :: IO Bool

  Returns whether the terminal supports strikethrough text.

  This is terminal-dependent and should make a best effort to determine whether this feature is supported, but even if the terminal advertises support (e.g. via terminfo) that might not be a reliable indicator of whether the feature will work as desired.

• outputColorMode :: ColorMode

  Returns how many colors the terminal supports.

Fields

• prevFattr :: Maybe FixedAttr
   
• prevOutputOps :: Maybe DisplayOps
   

Fields

• contextDevice :: Output
   
• contextRegion :: DisplayRegion

  Provide the bounds of the display context.

• writeMoveCursor :: Int -> Int -> Write

  Sets the output position to the specified row and column where the number of bytes required for the control codes can be specified seperate from the actual byte sequence.

• writeShowCursor :: Write
   
• writeHideCursor :: Write
   
• writeSetAttr :: Bool -> FixedAttr -> Attr -> DisplayAttrDiff -> Write
   
• writeDefaultAttr :: Bool -> Write

  Reset the display attributes to the default display attributes.

• writeRowEnd :: Write
   
• inlineHack :: IO ()

  See inlineHack