[css-fonts-4] How are duplicate "feature value blocks" treated in @font-feature-values?

[tabatkins]

If you have a single @font-feature-values rule with a duplicate "feature value block", are those blocks cascaded together or last-wins?

@font-feature-values foo {
  @swash { pretty: 1; }
  @swash { cool: 2; }
}

Does the above let me do font-feature-alternates: swash(pretty); and font-feature-alternates: swash(cool);, or just cool?

Same question between rules, too:

@font-feature-values foo {
  @swash { pretty: 1; }
}
@font-feature-values foo {
  @swash { cool: 2; }
}

---

In both of these cases, I presume that they cascade together; in other words, the only duplication we look out for is in the (family, feature, name) whole tuples, at which point last-wins.

[tabatkins]

I read down further and the second case (multiple rules defining stuff for the same feature type) is already addressed with a "yes". I'll go ahead and assume the first case is the same and close this. (I'm editting the text to say that already.)