S3 dispatch for primitive generics

I seem to recall reading that for primitive generics, S3 will dispatch
on class first, then on mode.  Unfortunately, I can't find the place
that I read this, and I don't trust my memory.

1) Is this correct?  Or is it dispatch on class, then on typeof? Or
something else?

2) Where is this documented?

Regards,
Richie

Learning R
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