[RangeReplaceableCollection] Use reserveCapacity in default append(contentsOf:) impl
#86043
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…pend(contentsOf:)` implementation)
MahdiBM
commented
Dec 15, 2025
| @inlinable | ||
| public mutating func append<S: Sequence>(contentsOf newElements: __owned S) | ||
| where S.Element == Element { | ||
| reserveCapacity(newElements.underestimatedCount) |
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I could use newElements.count(where: { _ in true }) to get the count as well.
LMK if you think I should do that.
Or even If I should do something more complicated, like using underestimatedCount by default, but if underestimatedCount is 0 then try count(where: { _ in true }) as well.
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Interesting. I just noticed this PR: #65927 Does this still apply? |
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Reading the PR it does sound like this still applies. |
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By a quick look, I think there are more places that could use this "optimization" of reserving-capacity beforehand.
I'm doing this PR for now, just to see if I'm missing something or if this is an acceptable change.