In the next chapter, you’ll move onto Common Lisp’s condition system, the Common Lisp analog to other languages’ exception and error handling systems.

1Of course, most folks realize it’s not worth getting that worked up over anything in a programming language and use it or not without a lot of angst. On the other hand, it’s interesting that these two features are the two features in Common Lisp that implement what are essentially domain-specific languages using a syntax not based on s-expressions. The syntax of **FORMAT**‘s control strings is character based, while the extended **LOOP** macro can be understood only in terms of the grammar of the **LOOP** keywords. That one of the common knocks on both **FORMAT** and **LOOP** is that they “aren’t Lispy enough” is evidence that Lispers really do like the s-expression syntax.

3To slightly confuse matters, most other I/O functions also accept **T** and **NIL** as stream designators but with a different meaning: as a stream designator, **T** designates the bidirectional stream ***TERMINAL-IO***, while **NIL** designates ***STANDARD-OUTPUT*** as an output stream and as an input stream.

4This variant on the ~C directive makes more sense on platforms like the Lisp Machines where key press events were represented by Lisp characters.

6Well, that’s what the language standard says. For some reason, perhaps rooted in a common ancestral code base, several Common Lisp implementations don’t implement this aspect of the ~F directive correctly.

7If you find “I saw zero elves” to be a bit clunky, you could use a slightly more elaborate format string that makes another use of ~:* like this: