bug#6448: `event-apply-modifier' EVENT arg accepts float then bails

[Chong Yidong]

MON KEY <monkey@sandpframing.com> writes:

> Can `read-event' return a float?
>
> If not, why does `event-apply-modifier' invoke the `numberp' predicate instead
> of `integerp'?
>
> e.g. these signals an error:
>
>  (event-apply-modifier 32.3 'shift 25 "<S-")
>  (event-apply-modifier (float (string-to-char "\C-s")) 'shift 25 "<S-")
>
> This is kosher:
>
>  (event-apply-modifier 19 'shift 25 "<S-")

I don't think this is a problem in real life.