SKIP suggests you're not using the result. Yet historical SKIP doesn't really do that:
rebol2> parse [1] [set x skip]
rebol2> x
== 1 ; How was this "skipped" exactly?
After contemplation of many possibilities for what this might be (including *, or <*>, or ?, or just plain period (.), I settled on <any>.
>> parse [1] [x: <any>]
>> x
== 1
I'm quite happy with it--especially in light of removing ANY as a looping combinator from the default combinator set. It brings ANY to its coherent systemic meaning of ANY-ONE-OF... as opposed to ANY-NUMBER-OF.
But @IngoHohmann suggested that SKIP might be related to ELIDE. So I tried:
>> uparse "ab" ["a" skip]
== "a"
This would make SKIP equivalent to ELIDE <any>.
But SKIP as ELIDE <ANY> IS RARELY USEFUL, AND CONFUSING
If you want ELIDE <ANY> just write that.
The general skip takes an argument of how much to skip, and having a PARSE analog to SKIP that takes no argument is just confusing.
It may be that SKIP taking an argument is worth having:
>> uparse "aaab" [skip (3) "b"]
== "b"
But then we have to decide what SKIP returns:
>> uparse "aaab" [skip (3)]
== ???
And you can say that particular case with 3 <any> and it's shorter.
Either Way, the Historical Use Is Pointless
So SKIP is not in UPARSE. Maybe it will have a reinvention some day with a new meaning.