Haskell 使用动态值扩展静态自动完成命令列表
我在Haskell中有以下程序,它从命令行获取输入并修改Haskell 使用动态值扩展静态自动完成命令列表,haskell,autocomplete,Haskell,Autocomplete,我在Haskell中有以下程序,它从命令行获取输入并修改mydata变量的状态: {-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, UndecidableInstances #-} import Text.Regex.PCRE import System.Console.Haskeline import System.IO import System.IO.Unsafe import Control.Monad.State.Stric
mydata
变量的状态:
{-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, UndecidableInstances #-}
import Text.Regex.PCRE
import System.Console.Haskeline
import System.IO
import System.IO.Unsafe
import Control.Monad.State.Strict
import qualified Data.ByteString.Char8 as B
import Data.Maybe
import Data.List
import qualified Data.Map as M
data MyDataState = MyDataState {
mydata :: [Int],
showEven :: Bool
} deriving (Show)
myfile :: FilePath
myfile = "data.txt"
defaultFlagValue :: Bool
defaultFlagValue = False
saveDataToFile :: [Int] -> IO ()
saveDataToFile _data = withFile myfile WriteMode $ \h -> hPutStr h (unwords $ map show _data)
{-# NOINLINE loadDataFromFile #-}
loadDataFromFile :: [Int]
loadDataFromFile = map read . words $ B.unpack $ unsafePerformIO $ B.readFile myfile
wordList = [":help", ":q", ":commands", ":show", ":save", ":edit", ":new", ":toggleShowEven"]
searchFunc :: String -> [Completion]
searchFunc str = map simpleCompletion $ filter (str `isPrefixOf`) (wordList)
mySettings :: Settings (StateT MyDataState IO)
mySettings = Settings { historyFile = Just "myhist"
, complete = completeWord Nothing " \t" $ return . searchFunc
, autoAddHistory = True
}
help :: InputT (StateT MyDataState IO) ()
help = liftIO $ mapM_ putStrLn
[ ""
, ":help - this help"
, ":q - quit"
, ":commands - list available commands"
, ""
]
commands :: InputT (StateT MyDataState IO) ()
commands = liftIO $ mapM_ putStrLn
[ ""
, ":show - display data"
, ":save - save results to file"
, ":edit - edit data"
, ":new - generate new element "
, ":toggleShowEven - toggle display of even elements"
, ""
]
toggleFlag :: InputT (StateT MyDataState IO) ()
toggleFlag = do
MyDataState mydata flag <- get
put $ MyDataState mydata (not flag)
instance MonadState s m => MonadState s (InputT m) where
get = lift get
put = lift . put
state = lift . state
parseInput :: String -> InputT (StateT MyDataState IO) ()
parseInput inp
| inp =~ "^\\:q" = return ()
| inp =~ "^\\:he" = help >> mainLoop
| inp =~ "^\\:commands" = commands >> mainLoop
| inp =~ "^\\:toggleShowEven" = toggleFlag >> mainLoop
| inp =~ "^\\:show" = do
MyDataState mydata showEven <- get
liftIO $ putStrLn $ unwords $ if showEven
then map show mydata
else map show $ filter odd mydata
mainLoop
| inp =~ "^\\:save" = do
MyDataState mydata _ <- get
liftIO $ saveDataToFile mydata
mainLoop
| inp =~ "^\\:load" = do
put (MyDataState loadDataFromFile defaultFlagValue)
mainLoop
| inp =~ "^\\:new" = do
MyDataState mydata showEven <- get -- reads the state
inputData <- getInputLine "\tEnter data: "
case inputData of
Nothing -> put ( MyDataState [0] showEven )
Just inputD ->
put $ if null mydata
then MyDataState [read inputD] showEven
else MyDataState (mydata ++ [read inputD]) showEven -- updates the state
mainLoop
| inp =~ ":" = do
outputStrLn $ "\nNo command \"" ++ inp ++ "\"\n"
mainLoop
| otherwise = handleInput inp
handleInput :: String -> InputT (StateT MyDataState IO) ()
handleInput inp = mainLoop
mainLoop :: InputT (StateT MyDataState IO ) ()
mainLoop = do
inp <- getInputLine "% "
maybe (return ()) parseInput inp
greet :: IO ()
greet = mapM_ putStrLn
[ ""
, " MyProgram"
, "=============================="
, "For help type \":help\""
, ""
]
main :: IO ((), MyDataState)
main = do
greet
runStateT (runInputT mySettings mainLoop) MyDataState {mydata = [] , showEven = defaultFlagValue}
正如您可能已经注意到的,此程序对典型命令使用命令行自动完成,例如:show
,:edit
,:new
,等等
我的问题如下。是否可以使用
MyDataState
中的值扩展可用于自动完成的命令列表(wordsList
variable)?例如,如果mydata
包含值1、2、3
,我希望它与可用于自动完成的命令一起显示-键入:Tab时,我将获得以下命令列表,而不是通过wordsList
静态定义::help
,:q
,:命令
,:显示
,:保存
,:编辑
,:新建
,:1
,,:2
,/strong>。我需要如何扩展searchFunc
定义以包括MyDataState
中定义的值?有可能吗 在设置
记录中,完成
字段的类型为CompletionFunc(StateT MyDataState IO)
,这意味着我们可以访问自动完成的状态
目前,mySettings
的定义使用
complete = completeWord Nothing " \t" $ return . searchFunc
这个返回
包装了一个纯函数,因此忽略了有状态上下文。我们可以将其替换为访问状态的计算:
complete = completeWord Nothing " \t" $ \str -> do
_data <- get
return (searchFunc _data str)
如果我替换返回。searchFunc
与返回。(\str->do\u data删除前导的返回。
。我修改了我的帖子,以显示代码应该是什么样子。如果我按照您的描述执行,我会遇到以下错误:无法将类型“[]”与“StateT MyDataState IO IO”匹配预期类型:CompletionFunc(StateT MyDataState IO IO)实际类型:CompletionFunc[]在记录的“完成”字段中;无法将类型“完成”与“[Completion]”匹配预期类型:[[Completion]]实际类型:[Completion]在'do'块的stmt中:searchFunc(u data str)
这是我在在线IDE中的代码,你可以调整并运行:哦,对不起,completeWord
需要一个(String->m[Completion])
类型的参数,因此searchFunc
的结果需要return
-ed:return(searchFunc(u data str。
complete = completeWord Nothing " \t" $ \str -> do
_data <- get
return (searchFunc _data str)
searchFunc :: MyDataState -> String -> [Completion]