RIO.ByteString.split 未按记录工作

Question

尝试 split docs 中的示例：

$ stack ghci
...
Prelude> :set -XOverloadedStrings
Prelude> import qualified RIO.ByteString as B
Prelude B> B.split 'a' "aXaXaXa"

<interactive>:3:9: error:
    • Couldn't match expected type ‘GHC.Word.Word8’
                  with actual type ‘Char’
    • In the first argument of ‘B.split’, namely ‘'a'’
      In the expression: B.split 'a' "aXaXaXa"
      In an equation for ‘it’: it = B.split 'a' "aXaXaXa"

我错过了什么？

Answer 1

文档取自split :: Char -> ByteString -> [ByteString] function of the Data.ByteString.Char8 module。这使用代码点 0-255 作为相应字节的 Char。

但是您可以改用字节值。例如 'a' 的字节值为 97，因此我们可以将其拆分为：

Prelude> :set -XOverloadedStrings
Prelude> import qualified RIO.ByteString as B
Prelude B> B.split 97 "aXaXaXa"
["","X","X","X",""]

RIO.ByteString.split 未按记录工作

RIO.ByteString.split not working as documented

haskell

rio