type Pool … // New returns a new [Pool] for T, and will use fn to construct new Ts when // the pool is empty. func New[T any](fn func() T) *Pool[T] { … } // Get gets a T from the pool, or creates a new one if the pool is empty. func (p *Pool[T]) Get() T { … } // Put returns x into the pool. func (p *Pool[T]) Put(x T) { … }