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使用 put子和 get子采取行动
原标题:Wrong IO actions order using putStr and getLine

我有以下法典:

main = do
    putStr "Test input : "
    content <- getLine
    putStrLn content

当我管理(有<条码>条码>,<>条码>)或汇编(第6.10.4条)时,结果如下:

asd
Test input : asd

为什么是<代码> 试验投入:作为在<条码>后印刷?

使用了putStr,getLine表示的产出不同于地雷。 I use putStrLn 该方案按预期运作(印本,然后迅速,印刷)。

它是在<代码>ghc中的ug,还是它应当如何工作?

最佳回答

这是因为吉西人不宜进行缓冲,而与格茨一起编纂的方案则按违约情况进行着缓冲。 你们可以这样做:

import System.IO
main = print =<< hGetBuffering stdout

在格西里,见NoBuffering <>/code>,而代谢则见LineBuffering。 由于新字体在<><>后/>上印有。 用户投入,即时值。

添加<代码>h 页: 1 SetBuffering rédout NoBuffering, 但该编码可能很坏。

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