Unsafe string and character functions.
charCodeAt :: Int -> String -> IntReturns the numeric Unicode value of the character at the given index.
Unsafe: throws runtime exception if the index is out of bounds.
charAt :: Int -> String -> CharReturns the character at the given index.
Unsafe: throws runtime exception if the index is out of bounds.
char :: String -> CharConverts a string of length 1 to a character.
Unsafe: throws runtime exception if length is not 1.