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zeropool

Oct 20, 2023

zeropool is a zero-allocation type-safe sync.Pool

// The function provided to zeropool.New() makes a Pool of a correct type using generics.
pool := zeropool.New(func() []byte { return nil })

// This is a []byte, no need to make type-assertion, no need to de-reference.
buf := pool.Get()

// This does not allocate.
pool.Put(buf)

Go provides sync.Pool pool implementation that allows storing any values (interface{} values). It is great but has two major drawbacks:

It's not type-safe, a type-assertion is needed on the elements provided by Get().

Since it stores interface{} values, it means that your value will escape1 to the heap unless you store a pointer (it would escape, but maybe just once).

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