Yi Config with Hello World Ex Command

HelloWorld.hs

module HelloWorld (helloWorld, parse) where

import Yi

-- For Ex command
import qualified Text.ParserCombinators.Parsec as P
import Yi.Keymap
import Yi.Keymap.Vim.Ex.Types
import qualified Yi.Keymap.Vim.Ex.Commands.Common as Common

-- A custom macro
helloWorld :: YiM ()
helloWorld = withBuffer $ insertN "Hello, world!"

-- helloWorld Ex Command
parse :: String -> Maybe ExCommand
parse = Common.parse $ do
          P.string "helloWorld"
          return $! Common.impureExCommand
                      { cmdAction = YiA $ helloWorld
                      , cmdShow = "helloWorld"
                      }

yi.hs

import Yi
import Yi.Keymap.Vim (keymapSet, mkKeymapSet, defVimConfig, vimExCommandParsers)
import qualified Yi.Mode.Haskell as Haskell
import Yi.Style
import Yi.Style.Library

import qualified HelloWorld as HelloWorld

main :: IO ()
main = yi $ defaultVimConfig
              { defaultKm = mkKeymapSet $ defVimConfig `override` \ super self -> super
                  { vimExCommandParsers = myExCmdParsers ++ vimExCommandParsers super }
              }

myExCmdParsers = [HelloWorld.parse]