/eve-cli

Terminal event handlers and rendering for `eve` programs

Primary LanguageHaskellOtherNOASSERTION

Eve.CLI

Eve.CLI provides eve compatible helpers for building CLI apps. It allows you to:

  • Respond to Keyboard, Mouse, and Resize Events
  • Render text/images to your terminal

Here's what it looks like:

module Main where

import Eve (eve_, App, exit)
import Eve.CLI (initCLI, onKeypress_, renderImage, Keypress(..))
import qualified Data.Text.Lazy as T
import qualified Graphics.Vty as V
import Control.Monad (void)

main :: IO ()
main = eve_ $ do
  initCLI
  onKeypress_ showKeypress
    where
      -- | Display the last key combination that you pressed on screen
      showKeypress :: Keypress -> App ()
      showKeypress (Keypress V.KEsc _) = exit
      showKeypress keypress = void . renderImage $ V.text V.defAttr . T.pack . show $ keypress

Events

Eve.CLI is a small wrapper on top of vty; so you'll also need to import Graphics.Vty in order to interact with most events. The following event listeners are provided:

  • onEvent
  • onKeypress
  • onMouseDown
  • onMouseUp
  • onResize
  • onPaste

See the hackage docs for more in depth API documentation.

Rendering

Currently Eve.CLI supports only rendering a Vty.Image; this means you can use any of Vty's image building combinators, then simply call renderImage with the image you've built.