doctest-parallel-0.3.0: src/Data/List/Extra.hs

module Data.List.Extra (trim) where

import Data.Char (isSpace)
import Data.List (dropWhileEnd)

-- | Remove spaces from either side of a string. A combination of 'trimEnd' and 'trimStart'.
--
-- > trim      "  hello   " == "hello"
-- > trimStart "  hello   " == "hello   "
-- > trimEnd   "  hello   " == "  hello"
-- > \s -> trim s == trimEnd (trimStart s)
trim :: String -> String
trim = trimEnd . trimStart

-- | Remove spaces from the start of a string, see 'trim'.
trimStart :: String -> String
trimStart = dropWhile isSpace

-- | Remove spaces from the end of a string, see 'trim'.
trimEnd :: String -> String
trimEnd = dropWhileEnd isSpace