(if (delivery-value :keep-debug-mode) :default nil)
This keyword is deprecated in favor of :clos-initarg-checking.
The value of the
:make-instance-keyword-check keyword controls whether
make-instance checks its initargs in the delivered application, and in LispWorks 6.1 this was extended to include checking in the other CLOS initializations.
:make-instance-argument-checking now does the same comprehensive checking as :clos-initarg-checking but is deprecated as its name is no longer accurate. Please use :clos-initarg-checking instead.
Affected by: :keep-debug-mode
LispWorks Delivery User Guide - 10 Aug 2017