[Haskell-cafe] 回复： Replace list item with list.

[Денис Мирзоев]

If you sure "z" is the last element of A you can use

init A ++ B

if it's somwhere in the middle consider

cocat $ map f A
  where
    f x
      | x == "z" = B
      | otherwise = [x]

On Sat, Nov 4, 2017 at 2:41 PM, Денис Мирзоев <nolane16 at gmail.com> wrote:

> If you sure "z" is the last element of A you can use
>
> init A ++ B
>
> if it's somwhere in the middle consider
>
> cocat $ map f A
>   where
>     f x
>       | x == "z" = B
>       | otherwise = [x]
>
> On Sat, Nov 4, 2017 at 1:57 PM, FlyingSheep <flyingsheep at qq.com> wrote:
>
>> (take 2 A) ++ B
>>
>> ------------------
>> 李 鹏
>> 四川大学计算机学院
>>
>>
>>
>> ------------------ 原始邮件 ------------------
>> *发件人:* "mirone"<saul-mirone at qq.com>;
>> *发送时间:* 2017年11月4日(星期六) 晚上6:48
>> *收件人:* "haskell-cafe"<haskell-cafe at haskell.org>;
>> *主题:* [Haskell-cafe] Replace list item with list.
>>
>> Hello everyone!
>> If I have a list A : ["x", "y", "z"]
>> and a list B: ["f", "g"].
>> Here is my question:
>> What's the simplest way to replace "z" in the list A by list B, and get
>> ["x", "y", "f", "g"] ?
>>
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>
>
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