Re: Revamping sit-for [Was: Lingering input pending with motif menu bar]

[Richard Stallman]

    It would be useful to know exactly what events will no longer make
    sit-for return -- then we could grep for those events and see if any
    lisp code uses sit-for to wait for one of those events.

Some of them, such as help-echo events, could be grepped for.  But
some kinds may not even show up at the Lisp level.  And other code
might not refer to them by name.  Therefore, I don't think such
grepping would be at all reliable.