Common Lisp the Language, 2nd Edition
[The contents of this section are still a subject of some debate within X3J13. The reader may wish to take this section with a grain of salt.-GLS]
Note that signaling a condition has no side effect on that condition, and that there is no dynamic state contained in a condition object. As such, it may at times be reasonable and appropriate to consider caching condition objects for repeated use, re-signaling conditions from within handlers, or saving conditions away somewhere and re-signaling them later.
For example, it may be desirable for the system to pre-allocate objects of type
storage-condition so that they can be signaled when needed without
attempting to allocate more storage.