format
  • FORMAT is Common Lisp's function for creating formatted text output. It is analogous to C's 'printf', but FORMAT can do a whole lot more.
  • An article, Advanced Use of Lisp's FORMAT Function, shows how to make full use of FORMAT's abilities. (The article was previously at lisp-p.org)
  • Drew McDermott has a good argument for not using FORMAT.
  • py-format has a lisp port of Python's str.format method, using the curly-brace {} notation.
  • A table comprehensively summarizing all FORMAT directives and the various arguments and modifiers they accept (along with further relevant information) is available.

Online Tutorial, Document