gtk:action-group-add-action (group action &optional accelerator)

group -- a gtk:action-group object
action -- a gtk:action object to add
accelerator -- a string with the optional accelerator for the action, in the format understood by the gtk:accelerator-parse function, or "" for no accelerator, or nil to use the stock accelerator

Adds an action to the action group and sets up the accelerator. If the accelerator argument is nil, this is the default value, attempts to use the accelerator associated with the stock ID of the action. Accel paths are set to <Actions>/group-name/action-name. The gtk:action-group-add-action function has been deprecated since version 3.10 and should not be used in newly written code.