key_state/[3,4]
key_state(+Displayable, +Keymap, -Key, -State) key_state(+Keymap, -Key, -State)
Allows the user to find out the state of a key in a keymap.
Displayable is a ProXL Displayable. If omitted, the default Display is used.
Keymap is a keymap, typically obtained by get_keyboard_attributes/N
.
Key is the name of a key.
State is either up
or down
.