我正在从 learnyouahaskell.com 学习 Haskell，有一个这样的例子：
search :: (Eq a) => [a] -> [a] -> Bool
search needle haystack =
let nlen = length needle
in foldl (\acc x -
> if take nlen x == needle then True else acc) False (tails haystack)
但是当用 GHC 尝试这段代码时，它给了我
error: parse error on input ‘-’
但当它像这样时它就起作用了：
search :: (Eq a) => [a] -> [a] -> Bool
search needle haystack =
let nlen = length needle
in foldl (\acc x -> if take nlen x == needle then True else acc) False (tails haystack)
Haskell 是否有允许多行 lambda 的功能，或者是我缺少的功能？
不要打破->
Just do:
search :: (Eq a) => [a] -> [a] -> Bool
search needle haystack =
let nlen = length needle
in foldl (\acc x ->
if take nlen x == needle then True else acc) False (tails haystack)
or
search :: (Eq a) => [a] -> [a] -> Bool
search needle haystack =
let nlen = length needle
in foldl (\acc x
-> if take nlen x == needle then True else acc) False (tails haystack)
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