quote adds double quotes around the string, replaces newline
characters with n, and escapes double quotes and backslashes
within the string. This is different from the behaviour of show:
> putStrLn $ show "\x2200"
"\8704"
> putStrLn $ quote "\x2200"
"∀"
(The code examples above have been tested using version 4.2.0.0 of the base library.)