The dspec system is the machinery underlying the way definitions are named in LispWorks. It supports program development by tracking the locations of definitions, and is also used in tracing and advising functions.
Dspecs are not expected to work in runtimes delivered at a delivery level greater than 0.
This chapter explains the concepts underlying dspecs and their use in tracking locations of definitions. For full details of the programming interface, see The DSPEC Package.
LispWorks User Guide and Reference Manual - 13 Feb 2015