sig
type crossing_mode = NotifyNormal | NotifyGrab | NotifyUngrab
type crossing_detail =
NotifyAncestor
| NotifyVirtual
| NotifyInferior
| NotifyNonlinear
| NotifyNonlinearVirtual
type crossing_state =
Button1Mask
| Button2Mask
| Button3Mask
| Button4Mask
| Button5Mask
| ShiftMask
| LockMask
| ControlMask
| Mod1Mask
| Mod2Mask
| Mod3Mask
| Mod4Mask
| Mod5Mask
end