I have a list ['%','&','/']. How can i convert it into the form [%,&开发者_如何学Python,/] ?
myShow :: [Char] -> String
myShow s = concat ["[", intersperse ',' s, "]"]
Use it like this:
putStrLn (myShow ['%','&','/']) -- prints [%,&,/]
But if you want this to work with show
and print
, you will have to define your own type:
data MyChar = MyChar Char
instance Show MyChar
where show (MyChar ch) = [ch]
And then operate on [MyChar]
rather than [Char]
:
let myList = map MyChar ['%','&','/']
-- ... do whatever you want with myList ...
print myList -- prints [%,&,/]
"[" ++ intercalate ',' list ++ "]"
intercalate
is declared in Data.List
.
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