I'd recommend downloading cl-interpol <http://weitz.de/cl-interpol/> it should give you what
you are looking for.

CL-USER 2 > (cl-interpol:enable-interpol
-syntax)

CL-USER 3 > #?"1 is less than ${most-positive-fixnum}"
"1 is less than 8388607"

Cheers,
 Sean.