What should the set of those classes been called?

[ClSlaid]

FYI, I've been drafting an RFC proposal about the observability of OpenDAL related to #527.

Reader, Writer and DirStreamer are utilities we used in OpenDAL for basic IOs, and I once liked to call them "basic IO interfaces", but calling it "BII" or "BIOI" for short is kind of strange. Meanwhile, "basic IO objects (BIO)" may confuse my Grammarly when writing "BIOs".

So I gave up thinking and asked for better names here.

[Xuanwo]

Writer will be deprecated in the subsequent releases, so you don't need to worry about that.

For other structs, I think it's OK to always refer to Reader and DirStreamer.