Complex generic constraints can't be overridden with `SKIP DECLARE`

[dfabulich]

Regarding skiptools/skip-ui#210 I was unable to get this declaration to transpile:

// SKIP DECLARE: public fun <K: PreferenceKey<V>, V: Any> View.onPreferenceChange(key: KClass<K>, perform: (V) -> Unit): View
public func onPreferenceChange<K>(
        _ key: K.Type = K.self,
        perform action: @escaping (
            K.Value
        ) -> Void
    ) -> some View where K : PreferenceKey, K.Value : Equatable {

The transpiler kept objecting to the K.Value : Equatable clause of the where. That would be fine if the SKIP DECLARE comment would allow me to use an alternate declaration, but Skip refused to transpile this code even with SKIP DECLARE.

IMO, SKIP DECLARE should make the transpiler stop complaining about the declaration.

[marcprux]

As mentioned in the similar issue report at https://github.com/orgs/skiptools/discussions/514, the problem is that Skip errors out before it even processes the SKIP DECLARE. But you might be able to externalize generic constraint in a typealias to work around it. Something like this:

#if !SKIP
typealias PreferenceKeyOf<K: PreferenceKey> = K where K.Value : Equatable
#else
typealias PreferenceKeyOf = PreferenceKey
#endif

func onPreferenceChange<K>(_ key: K.Type = K.self, perform action: @escaping (PreferenceKeyOf<K>.Value) -> Void) -> some View {
}

[dfabulich]

Is this something y'all could fix?

If not, could it be documented near SKIP DECLARE? https://skip.tools/docs/platformcustomization/#skip-comments