A define-modify-macro lambda list is used by define-modify-macro.
A define-modify-macro lambda list can contain the lambda list keywords shown in the next figure.
&optional &rest
Figure 3-20. Lambda List Keywords used by Define-modify-macro Lambda Lists
Define-modify-macro lambda lists are similar to ordinary lambda lists, but do not support keyword arguments. define-modify-macro has no need match keyword arguments, and a rest parameter is sufficient. Aux variables are also not supported, since define-modify-macro has no body forms which could refer to such bindings. See the macro define-modify-macro.