A concurrent data structure that exposes a linear sequence of R resources as a single cats.effect.kernel.Resource in F without accumulation.

A NonEmptyHotswap is allocated within a cats.effect.kernel.Resource that dictates the scope of its lifetime. After creation, a Resource[F, R] can be swapped in by calling swap. The newly acquired resource is returned and is released either when the NonEmptyHotswap is finalized or upon the next call to swap, whichever occurs first.

The following diagram illustrates the linear allocation and release of three resources r1, r2, and r3 cycled through NonEmptyHotswap:

create(r1) ----- swap(r2) ---- swap(r3) ---- X
|                |             |             |
r1 acquired      |             |             |
                 r2 acquired   |             |
                 r1 released   r3 acquired   |
                               r2 released   |
                                             r3 released

NonEmptyHotswap is particularly useful when working with effects that cycle through resources, like writing bytes to files or rotating files every N bytes or M seconds. Without NonEmptyHotswap, such effects leak resources: on each file rotation, a file handle or some internal resource handle accumulates. With NonEmptyHotswap, the only registered resource is the NonEmptyHotswap itself, and each file is swapped in only after swapping the previous one out.

Replaces the deprecated Hotswap with a safer API.