list - 是否有任何 haskell 函数可以将列表与分隔符连接起来？

Question

是否有一个函数可以用分隔符连接列表的元素？例如:

> foobar " " ["is","there","such","a","function","?"]
["is there such a function ?"]

感谢您的回复!

Answer 1

是的，there is :

Prelude> import Data.List
Prelude Data.List> intercalate " " ["is","there","such","a","function","?"]
"is there such a function ?"

intersperse有点笼统:

Prelude> import Data.List
Prelude Data.List> concat (intersperse " " ["is","there","such","a","function","?"])
"is there such a function ?"

此外，对于您想要使用空格字符连接的特定情况，有 unwords :

Prelude> unwords ["is","there","such","a","function","?"]
"is there such a function ?"

unlines工作原理类似，只是使用换行符对字符串进行内爆，并且换行符也添加到末尾。 (这使得它对于序列化文本文件非常有用，文本文件必须按照 POSIX 标准结尾并带有尾随换行符)