Every event has an event type, which classifies the event for key binding purposes. For a keyboard event, the event type equals the event value; thus, the event type for a character is the character, and the event type for a function key symbol is the symbol itself. For events that are lists, the event type is the symbol in the CAR of the list. Thus, the event type is always a symbol or a character.
Two events of the same type are equivalent where key bindings are concerned; thus, they always run the same command. That does not necessarily mean they do the same things, however, as some commands look at the whole event to decide what to do. For example, some commands use the location of a mouse event to decide where in the buffer to act.
Sometimes broader classifications of events are useful. For example, you might want to ask whether an event involved the META key, regardless of which other key or mouse button was used.
provided to get such information conveniently.
This function returns a list of the modifiers that event has. The
modifiers are symbols; they include
super. In addition,
the modifiers list of a mouse event symbol always contains one of
down. For double or triple
events, it also contains
The argument event may be an entire event object, or just an
event type. If event is a symbol that has never been used in an
event that has been read as input in the current Emacs session, then
event-modifiers can return
nil, even when event
actually has modifiers.
Here are some examples:
(event-modifiers ?a) ⇒ nil (event-modifiers ?A) ⇒ (shift) (event-modifiers ?\C-a) ⇒ (control) (event-modifiers ?\C-%) ⇒ (control) (event-modifiers ?\C-\S-a) ⇒ (control shift) (event-modifiers 'f5) ⇒ nil (event-modifiers 's-f5) ⇒ (super) (event-modifiers 'M-S-f5) ⇒ (meta shift) (event-modifiers 'mouse-1) ⇒ (click) (event-modifiers 'down-mouse-1) ⇒ (down)
The modifiers list for a click event explicitly contains
but the event symbol name itself does not contain ‘click’.
Similarly, the modifiers list for an ASCII control
character, such as ‘C-a’, contains
control, even though
reading such an event via
read-char will return the value 1
with the control modifier bit removed.
This function returns the key or mouse button that event
describes, with all modifiers removed. The event argument is as
event-modifiers. For example:
(event-basic-type ?a) ⇒ 97 (event-basic-type ?A) ⇒ 97 (event-basic-type ?\C-a) ⇒ 97 (event-basic-type ?\C-\S-a) ⇒ 97 (event-basic-type 'f5) ⇒ f5 (event-basic-type 's-f5) ⇒ f5 (event-basic-type 'M-S-f5) ⇒ f5 (event-basic-type 'down-mouse-1) ⇒ mouse-1