content: --------------------------------------------------------------------------------
  -- MIT License
  --
  -- Copyright (C) 2023 Duck McSouls <quacksouls [AT] gmail [DOT] com>
  --
  -- Permission is hereby granted, free of charge, to any person obtaining a copy
  -- of this software and associated documentation files (the "Software"), to deal
  -- in the Software without restriction, including without limitation the rights
  -- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  -- copies of the Software, and to permit persons to whom the Software is
  -- furnished to do so, subject to the following conditions:
  --
  -- The above copyright notice and this permission notice shall be included in
  -- all copies or substantial portions of the Software.
  --
  -- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  -- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  -- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  -- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  -- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  -- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  -- SOFTWARE.
  --------------------------------------------------------------------------------
  
  import Data.Char
  import Text.Printf
  
  -- | Convert the first character of a string to uppercase.
  capitalize :: String -> String
  capitalize str = (toUpper $ head str) : (tail str)
  
  -- | Remove the first and last characters of a string, reverse the
  -- string, then capitalize the result.
  chopSuey :: String -> String
  chopSuey str = do
      let torso = init . tail
      capitalize . reverse $ torso str
  
  -- | Same as chopSuey, but simplified.
  chopSueyB :: String -> String
  chopSueyB str = capitalize . reverse . init . tail $ str
  
  -- | Same as chopSueyB, but using only function application notation.
  chopSueyC :: String -> String
  chopSueyC str = capitalize $ reverse $ init $ tail $ str
  
  -- | Various manipulations of a string.
  main = do
      let a = "!yyyay"
      let b = "clive evils"
      let c = "8caterpillar-"
      let resulta = chopSuey a == chopSueyB a && chopSuey a == chopSueyC a
      let resultb = chopSuey b == chopSueyB b && chopSuey b == chopSueyC b
      let resultc = chopSuey c == chopSueyB c && chopSuey c == chopSueyC c
      printf "%s -> %s: %s\n" a (chopSuey a) $ show resulta
      printf "%s -> %s: %s\n" b (chopSuey b) $ show resultb
      printf "%s -> %s: %s\n" c (chopSuey c) $ show resultc
  