Action lists are defined using the define-action-list macro, and are undefined using the undefine-action-list. It is also possible to make unnamed, unregistered lists using make-unregistered-action-list.
When defining an action-list, the user may provide an associated execution-function. When executing the action-list, this user-defined execution-function is used instead of the default execution-function, to map over and "execute" the action-list's action-items. The macro with-action-list-mapping provides facilities to map over action-items (that is, their corresponding "data"). In addition, the macro with-action-list-mapping provides a simple mechanism to trap errors and print warnings while executing each action-item.
Actions are added to an action list using define-action, and are removed using undefine-action.
LispWorks User Guide and Reference Manual - 21 Dec 2011