Martin Buchholz <martin(a)xemacs.org&gt; writes: This is, I assume, Common Lisp? Because in XEmacs Lisp characters and markers are also allowed: In addition to numbers, all of the following functions also accept characters and markers as arguments, and treat them as their number equivalents. What "number equivalent" means is open for debate, but equality should remain well-defined in those terms. char= is all nice, but then we'd also need char<, char>, char<= etc. That sounds ugly. How does CL collate characters? Fixable by changing CHECK_CHAR_COERCE_INT to CHECK_CHAR. Totally.