23.3.3 Side-effects of stepping
When the Stepper steps a definition for the first time, it evaluates it.
This will not normally alter the behavior of your program, but there are three situations where this will cause unexpected behavior:
-
The code is loaded from a fasl file which is not compatible with the corresponding source file.
-
The source relies on compile-time side-effects of forms preceding it in the file.
-
The defining form has other side effects. This is unlikely to matter for simple definers such as
defun
and
defmethod
.
Common LispWorks User Guide (Macintosh version) - 21 Feb 2008