A CLOS instance.
The keyword arguments control which type of access cause a break and are interpreted as described for trace-on-access.
A useful debugging function which causes access to
to break to the debugger. Accesses include calls to
and also accessor functions defined by the class of
. Other instances of the same class are unaffected.
You can remove the break by calling unbreak-on-access.
Note: this function is deprecated. You should now call trace-on-access with