shell: Quote string with single quotes rather than backslashes

How can I quote a string with single quotes? Eg, I can do: $ printf "%q\n" 'two words' two\ words $ Is there a way to get a single- (or double-) quoted string as output, ie: $ MAGIC 'two words' 'two words' $ I find the single-quoted version much easier to read. I'd like an answer which works for {ba,z}sh. POSIX shell would be a bonus.