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by steveklabnik 2958 days ago
Not today, but it's coming. This kind of thing does work on nightly.
1 comments

I was mostly excited about slice patterns because of a pattern I wanted to be able to write:

    some_collection.windows(2).filter(|[a,b]|a==b).map(|[a, _] |a).collect();
Turns out the compiler rejects that with a "refutable pattern" error, because the args part of the filter/map closures do not handle the situation where the slice could be empty, which AFAIK can not occur when using windows/chunks/...

Maybe there has to be some special case handling for this pattern to be valid?

Hm, interesting. I think this isn't possible without integer generics.
Because the pattern in the filter closure would have to be generic over the length or am I mistaken?