如何在 ghci 提示符下不显示重复的模块

Question

目前，这就是我的GHCI提示的样子：

，我想做到这一点，以便我的提示不显示重复模块，如下所示：

​T真的弄清楚了如何。我的配置（ghci.conf）文件的内容如下所示：

:set +m

import qualified IPPrint
import qualified Language.Haskell.HsColour as HsColour
import qualified Language.Haskell.HsColour.Colourise as HsColour
import qualified Language.Haskell.HsColour.Output as HsColour

let myColourPrefs = HsColour.defaultColourPrefs { HsColour.conid = [HsColour.Foreground HsColour.Yellow, HsColour.Bold], HsColour.conop = [HsColour.Foreground HsColour.Yellow], HsColour.string = [HsColour.Foreground HsColour.Green], HsColour.char = [HsColour.Foreground HsColour.Cyan], HsColour.number = [HsColour.Foreground HsColour.Red, HsColour.Bold], HsColour.layout = [HsColour.Foreground HsColour.White], HsColour.keyglyph = [HsColour.Foreground HsColour.White] }

let myPrint = putStrLn . HsColour.hscolour (HsColour.TTYg HsColour.XTerm256Compatible) myColourPrefs False False "" False . IPPrint.pshow

:set -interactive-print=myPrint

:{
prompter :: [String] -> Int -> IO String
prompter modules line = return $
    concat [ "\ESC[33m\STX[Module(s): "
           -- this is the only line that changed
           , Data.List.intercalate ", " $ zipWith (\n m -> concat [show n, ".", m]) [1..] modules
           , "]\ESC[0m\STX\n \ESC[38;5;86m\STX\x03BB > \ESC[0m\STX"
           ]   
:}
:set prompt-function prompter
clear = putStr "\ESC[2J\ESC[H"

谢谢您。

Answer 1

通过使用 nub 从列表中删除重复元素（请参阅：），我能够从模块列表中删除重复元素，如下所示：

为了做代码，代码也必须必须被修改为：

:{
prompter :: [String] -> Int -> IO String
prompter modules line = return $
    concat [ "\ESC[33m\STX[Module(s): "
           -- this is the only line that changed
           , Data.List.intercalate ", " $ zipWith (\n m -> concat [show n, ".", m]) [1..] (nub modules)
           , "]\ESC[0m\STX\n \ESC[38;5;86m\STX\x03BB > \ESC[0m\STX"
           ]   
:}

并且由于 nub 是数据的一部分。清单模块，我还必须包括：

import Data.List