Feature Request: Seekable Buffer ("SeekBuf") and cursor/iterator support about bytes HOT 2 OPEN

That's a great idea! And a very simple change (already added to the PR), thank you, it was definitely an oversight to not include a Clone impl for BufCursor.

from bytes.

Great PR, this is very much something I was looking for in bytes. If for whatever reason this isn't accepted, I would suggest it's worthwhile packaging it as a third-party "add-on" crate.

Regarding using BufCursor for parsing and lookahead - would it be possible to implement Clone for its iterator state?

This would allow passing cheap clones of a BufCursors to sub-functions in a main parsing loop, allowing us to eagerly peek at bytes to return a successful parse or continue on to the next parsing attempt, without disturbing the main cursor's position.

I note this could be achieved at present by checking cursor_position and re-slicing the main buffer into a new cursor each time, but in terms of elegance and transparency I feel like simply cloning the BufCursor would be far superior.

Edit: Okay, I just realised this is what subcursors are for, but it's still kind of suboptimal to deal with n levels of nested BufCursor<BufCursor<...>.

from bytes.