Getting an io.Reader over a byte slice is a useful tool, but the primary use case for io.Reader is streaming stuff from the network or file system. In this con

Getting an io.Reader over a byte slice is a useful tool, but the primary use case for io.Reader is streaming stuff from the network or file system. In this context, you can either have the io.Reader do a copy without allocating anything (take in a slice managed by the caller), or allocate and return a slice. There isn't really a middle ground here.