The keyword arguments control which type of access are traced:
Non-
nil
means trace reading a slot. The default is
t
.
Non-
nil
means trace writing a slot. The default is
t
.
t
means trace access to all slots, otherwise this should be a list of symbols which are the slot-names on which to trace access. The default is
t
.
When non-
nil
, the debugger is entered. When
nil
, messages are printed to
*trace-output*
.
A common use of this function is to find where a slot is being changed in a complex program.
A useful debugging function which causes access to
instance
to invoke the trace facilities. Accesses include calls to
slot-value
and accessor functions defined by the class of
instance
. Other instances of the same class are unaffected and your can remove the trace by calling untrace-on-access. Breaks to the debugger when a traced slot in
instance
is accessed with
break
non-
nil
.
This function, when used with the break keyword, replaces the deprecated function break-on-access.