Char to string function

前端 未结 4 364
感情败类
感情败类 2021-01-03 18:30

I have a very simple question: Given a function accepting a char and returning a string

test :: Char -> [String]

how can one convert the

相关标签:
4条回答
  • 2021-01-03 19:13

    Another way would be using

    return . return
    

    Since return for lists is defined as :[]

    0 讨论(0)
  • 2021-01-03 19:25

    In Haskell String is an alias for [Char]:

    type String = [Char]
    

    If you just want a function that converts a single char to a string you could e.g. do

    charToString :: Char -> String
    charToString c = [c]
    

    If you prefer pointfree style you could also write

    charToString :: Char -> String
    charToString = (:[])
    
    0 讨论(0)
  • 2021-01-03 19:25

    Note that you can convert any type implementing the Show type class to a string using show:

    (Show a) => a -> String
    

    Because Char implements this, the function is already written for you!

    0 讨论(0)
  • 2021-01-03 19:29

    A String is just a [Char]

    But that's just a nice way of saying

    'H':'E':'L':'L':'O':[]
    

    So to make it a [String] we could do:

    ['H':'E':'L':'L':'O':[]]
    
    0 讨论(0)
提交回复
热议问题