Upgrade to Winnow 0.7

[epage]

FYI as this doesn't use cut_err or Partial, you could switch away from ErrMode for some potential simplification and performance improvements.

I think it should just be

1. Remove ErrMode
2. Switch from ModalParser to Parser
3. Switch from ModalResult to winnow::Result

However, it'd be harder to undo it (picking apart which Results need to be ModalResults) so I held off on it from this PR

[Byron]

Thanks a lot for your tremendous help with winnow updates, it's much appreciated!

It seems using winnow::Result is lighter as it doesn't include ErrMode, so it might be good for performance improvements. For now I don't know what that would do to the error output, but it seems that can be maintained as is.

Additionally I have left a comment with a question on how to improve a particular piece of code, hoping you find the time to take a look.

Thanks again.

[Byron]

This change was introduced in #1439 and I wonder if this there isn't an 'packagiomatic' way of writing this. This code implements the parser by hand, but that was done merely due to lack of knowledge on how to use winnow primitives.

Is there anything that could be done to make it nicer?

[epage]

The main challenge is the rfind, right? I've not thought of a good way to handle cases like that.

If its parsing within the \n delimited range, there is and_then, like take_until(0.., b'\n').and_then(parser).

[Byron]

Yes, it's the rfind() to assure it finds the right-most > as delimiter, within the line boundary.

[tisonkun]

I happened to look into this patch and would like to share some thoughts on ModalResult vs Result.

1. Currently, the gix_actor::identity::decode::identity parser returns ErrMode inline, so ModalResult and ModalParser are still needed.
2. However, the identity parser doesn't used in alt/opt, so perhaps directly returning an error without the ErrMode wrapper is possible. (won't hurt error reporting, in theory)
3. But this is like a one-way door as mentioned in the description ("harder to undo it").

Back to the reason I jump into this patch: this is the final winnow 0.6 dependency in the tree of my application, so I'd expect a new release to eliminate that :D

[epage]

But this is like a one-way door as mentioned in the description ("harder to undo it").

I do see it less likely that gitoxide will need ErrMode. Gitoxide is mostly focused on binary format parsing. cut_err is mostly important when wanting to improve the quality of error messages which is usually for parsing text.

[epage]

Oh, #1439 added Cut, nm.