Haskell string to list

Question

Possible Duplicate:
convert string list to int list in haskell

I have a string 12345. How can I show it in list form like [1,2,3,4,5]? And also what if i have a string like ##%%? I can't convert it to Int. How can view it in the form [#,#,%,%]?

Solution 1

Use intersperse

myShow :: String -> String
myShow s = concat ["[", intersperse ',' s, "]"]

Solution 2

import Data.Char (digitToInt)

map digitToInt "12345"

Solution 3

You should map the function read x::Int to each of the elements of the string as a list of chars:

map (\x -> read [x]::Int) "1234"

If you have non-digit characters you should filter it first like this:

import Data.Char
map (\x -> read [x]::Int) (filter (\x -> isDigit x) "1234##56")

That results in:

[1,2,3,4,5,6]

Solution 4

Have you taken a look at this answer? Convert string list to int list

A String is just a list of characters in Haskell after all. :)

Solution 5

Try using splitEvery with length 1

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Comments

[thetux4]

This works but what if i have a string like "##%%" ?

[Santiago Alessandri]

This counts that the string is made up by digits. If you want to filter the characters that are not digits you should use a filter. I will edit the answer

[thetux4]

I changed my question as well. Actually i don't want to split nondigits. I want to view them in list form.

[thetux4]

I checked it but when i try to convert a string like "&%" it gives parse error.