Create a Chunk from an IterableOnce #2722
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| else { | ||
| val head = itr.next() | ||
| if (itr.hasNext) { | ||
| val bldr = collection.mutable.Buffer.newBuilder[O] |
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According to this
https://github.com/typelevel/fs2/pull/2720/files#diff-e8fdf3ccd3d2479432355b3abf34a16cd548373afeddeaf231b8d8a1147b1d48R115
ArrayBuilder shows x2 performance compared to mutable.Buffer, shouldn't we change a type of builder used here?
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In those cases we have the (expected) size, we don't in this case.
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ArrayBuilder should still beat mutable buffer though, even without a size hint.
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Using ArrayBuilder requires us to add a ClassTag constraint, I don't think that is something that we want?
That would mean that we couldn't use it in iterable and chain.
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Merge the main branch in to this PR and then use makeArrayBuilder[Any]. We'll have to cast the resulting chunk back to a Chunk[A] just like we do in methods like filter.
| @@ -596,18 +596,24 @@ object Chunk | |||
| case ix: GIndexedSeq[O] => indexedSeq(ix) | |||
| case _ => | |||
| if (i.isEmpty) empty | |||
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emptiness gets checked in iterableOnce, can we remove this check from here and L626?
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Now the implementation has changed and it's an optimization. Thus, the comment is resolved.
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I already forgot |
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Thanks! |
The implementation is basically the one from
iterableandchain.I replaced the implementations in
iterableandchainwith a call toiterableOnce. This does add anIterator#isEmptycall.