DEFVAR_LISP ("last-command", &last_command,
"The last command executed. Normally a symbol with a function definition,\n\
but can be whatever was found in the keymap, or whatever the variable\n\
-`this-command' was set to by that command.");
+`this-command' was set to by that command.\n\
+\n\
+The value `mode-exit' is special; it means that the previous command\n\
+read an event that told it to exit, and it did so and unread that event.\n\
+In other words, the present command is the event that made the previous\n\
+command exit.\n\
+\n\
+The value `kill-region' is special; it means that the previous command\n\
+was a kill command.");
last_command = Qnil;
DEFVAR_LISP ("this-command", &this_command,