Copyright	Daniel Mendler (c) 2016
License	MIT (see the file LICENSE)
Maintainer	mail@daniel-mendler.de
Stability	experimental
Portability	portable
Safe Haskell	Safe
Language	Haskell2010

System.Console.Style

Description

This library provides styled text output using ANSI escape sequences. The main feature is that the library keeps track of a stack of the active styles using a state monad. This makes it easy to use this library for a pretty printer with nested annotations, e.g., wl-pprint-console.

Warning: Windows support is currently not implemented, but is planned (by using ansi-terminal or the ffi).

Example:

basicExample :: IO ()
basicExample = runWithStyle [FgColor Blue] $ do
  withStyle [Bold] $ liftIO $ putStr "Bold Blue"

  setStyle [Save, Italic, BgColor Red]
  liftIO $ putStr "Italic Red"
  setStyle [Restore]

  setStyle [Under]
  liftIO $ putStr "Under Blue"
  setStyle [Reset]

  liftIO $ putStrLn "Normal output"

For many more examples, see the Example.hs file.

Synopsis

Documentation

data Color #

Console color

Constructors

DefaultColor	Default terminal color (terminal specific)
Black
Red
Green
Yellow
Blue
Magenta
Cyan
White
DullBlack
DullRed
DullGreen
DullYellow
DullBlue
DullMagenta
DullCyan
DullWhite
Color256 !Word8	Color from 256 color scheme. Color is automatically reduced to 8 colors for less capable terminals.
RGB !Word8 !Word8 !Word8	True color. Color is automatically reduced to 256 or 8 colors for less capable terminals.

Instances

Eq Color #
Methods (==) :: Color -> Color -> Bool # (/=) :: Color -> Color -> Bool #
Ord Color #
Methods compare :: Color -> Color -> Ordering # (<) :: Color -> Color -> Bool # (<=) :: Color -> Color -> Bool # (>) :: Color -> Color -> Bool # (>=) :: Color -> Color -> Bool # max :: Color -> Color -> Color # min :: Color -> Color -> Color #
Show Color #
Methods showsPrec :: Int -> Color -> ShowS # show :: Color -> String # showList :: [Color] -> ShowS #

class HasStyle s where #

State accessor for the Style

Minimal complete definition

getStyle, putStyle

Methods

getStyle :: s -> Style #

putStyle :: Style -> s -> s #

Instances

HasStyle Style #
Methods getStyle :: Style -> Style # putStyle :: Style -> Style -> Style #

data SetStyle #

Style commands

Constructors

Bold	Bold font
NotBold	Normal-weight font
Italic	Italic font
NotItalic	Non-italic font
Under	Underlined text
NotUnder	Text without underline
Invert	Invert foreground and background color
NotInvert	Deactivate color inversion
Save	Save style to stack
Restore	Restore style from stack
Reset	Reset to default style
Blink	Activate blinking
NotBlink	Deactivate blinking
FgColor !Color
BgColor !Color

Instances

Eq SetStyle #
Methods (==) :: SetStyle -> SetStyle -> Bool # (/=) :: SetStyle -> SetStyle -> Bool #
Ord SetStyle #
Methods compare :: SetStyle -> SetStyle -> Ordering # (<) :: SetStyle -> SetStyle -> Bool # (<=) :: SetStyle -> SetStyle -> Bool # (>) :: SetStyle -> SetStyle -> Bool # (>=) :: SetStyle -> SetStyle -> Bool # max :: SetStyle -> SetStyle -> SetStyle # min :: SetStyle -> SetStyle -> SetStyle #
Show SetStyle #
Methods showsPrec :: Int -> SetStyle -> ShowS # show :: SetStyle -> String # showList :: [SetStyle] -> ShowS #

data Style #

Abstract state datatype which keeps a stack of the applied styles.

Instances

HasStyle Style #
Methods getStyle :: Style -> Style # putStyle :: Style -> Style -> Style #

data Term #

Terminal type. For less capable terminals the color depth is automatically reduced.

Constructors

TermDumb	Dumb terminal - no color output
Term8	8 colors supported
Term256	256 colors supported
TermRGB	True colors supported
TermWin	Windows terminal. Will use emulation (Not yet implemented).

Instances

Eq Term #
Methods (==) :: Term -> Term -> Bool # (/=) :: Term -> Term -> Bool #
Show Term #
Methods showsPrec :: Int -> Term -> ShowS # show :: Term -> String # showList :: [Term] -> ShowS #

defaultStyle :: Term -> Style #

The function (defaultStyle term) returns the default Style configured with terminal type term.

hDefaultStyle :: Handle -> Term -> Style #

(hDefaultStyle handle term) return the default (initial) Style configured with the file handlehandle and terminal type term@.

Every Style has a single associated handle.

hGetTerm :: MonadIO m => Handle -> m Term #

The action (hGetTerm handle) determines the terminal type of the file handle.

The terminal type is determined by checking if the file handle points to a device and by looking at the $TERM environment variable.

hRunStyle :: MonadIO m => Handle -> StateT Style m a -> m a #

The action (hRunStyle handle action) runs the StateT monad transformer providing the active Style for the given action.

hRunWithStyle :: (MonadIO m, Foldable f) => Handle -> f SetStyle -> StateT Style m a -> m a #

The action (hRunWithStyle handle cmd action) runs the StateT monad transformer providing the active Style for the given action.

The output on handle within the action is modified by the given StyleSet commands cmd. The Style is restored to the defaults afterwards.

runStyle :: Term -> State Style a -> a #

The action (runStyle term action) runs the State monad providing the active Style for the given action.

runStyleT :: Monad m => Term -> StateT Style m a -> m a #

The action (runStyleT term action) runs the StateT monad transformer providing the active Style for the given action.

runWithStyle :: (MonadIO m, Foldable f) => f SetStyle -> StateT Style m a -> m a #

The action (runWithStyle cmd action) runs the StateT monad transformer providing the active Style for the given action.

The output on stdout within the action is modified by the given StyleSet commands cmd. The Style is restored to the defaults afterwards.

setStyle :: (MonadIO m, MonadState s m, HasStyle s, Foldable f) => f SetStyle -> m () #

The action (setStyle cmd) modifies the active Style by executing the StyleSet commands cmd.

The style changes are applied immediately.

setStyleCode :: (MonadState s m, HasStyle s, Foldable f) => f SetStyle -> m String #

The action (styleCode cmd) returns the ANSI code corresponding to the StyleSet commands cmd.

withStyle :: (MonadIO m, MonadState s m, HasStyle s, Foldable f) => f SetStyle -> m a -> m a #

The action (withStyle cmd action) executes the action with the active Style modified by the StyleSet commands cmd.

The style is restored to the previous Style afterwards.

changeStyle :: (MonadState s m, HasStyle s, Foldable f) => f SetStyle -> m () #

The action (changeStyle cmd) modifies the active Style by executing the StyleSet commands cmd without applying the changes.

You have to call applyStyle or applyStyleCode afterwards!

applyStyle :: (MonadIO m, MonadState s m, HasStyle s) => m () #

The action applyStyle applies the latest style changes.

applyStyleCode :: (MonadState s m, HasStyle s) => m String #

The action applyStyleCode returns the ANSI code for the latest style changes.