v4.1.0

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• New data structure: UMPSCQueue #​168
• Speed up LoadAndDelete and Delete in case of non-existing Map key #​167
• Parallel Map resize #​170

UMPSCQueue is meant to serve as a replacement for a channel. However, crucially, it has infinite capacity. This is a very bad idea in many cases as it means that it never exhibits backpressure. In other words, if nothing is consuming elements from the queue, it will eventually consume all available memory and crash the process. However, there are also cases where this is desired behavior as it means the queue will dynamically allocate more memory to store temporary bursts, allowing producers to never block while the consumer catches up.

From now on, Map spawns additional goroutines to speed up resizing the hash table. This can be disabled when creating a Map with the new WithSerialResize setting:

m := xsync.NewMap[int, int](xsync.WithSerialResize())
// resize will take place on the current goroutine only
for i := 0; i < 10000; i++ {
	m.Store(i, i)
}

Thanks @​PapaCharlie and @​llxisdsh for the contributions!

v4.0.0

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• Minimal Golang version is now 1.24.
• All non-generic data structures are now removed. Generic versions should be used instead - they use the old names, but type aliases are present to simplify v3-to-v4 code migration.
• MapOf's hasher API is gone. The default and only hash function is now based on maphash.Comparable.
• Map's Compute API now supports no-op (cancel) compute operation.

Thanks @​PapaCharlie for making this release happen

Migration notes

• The old *Of types are kept as type aliases for the renamed data structures to simplify the migration, e.g. MapOf is an alias for Map.
• NewMapOfPresized function is gone. NewMap combined with WithPresize should be used instead.
• Map.Compute method now expects valueFn to return a ComputeOp value instead of a boolean flag. That's to support compute operation cancellation, so that the call does nothing.
• Map.LoadOrTryCompute method is renamed to LoadOrCompute. The old LoadOrCompute method is removed as it was redundant.