bstr VS rust-semverver

Libraries for a lot of this stuff exist (albeit in many cases not very mature yet):

- https://github.com/pop-os/cosmic-text does text layout (which Taffy explicitly considers out of scope)

- https://github.com/AccessKit/accesskit does accessibility

- https://github.com/servo/rust-cssparser does value-agnostic CSS parsing (it will parse the general syntax but leaves value parsing up to the user, meaning you can easily add support for whatever properties you what). Libraries like https://github.com/parcel-bundler/lightningcss implement parsing for the standard css properties.

- There are crates like https://github.com/BurntSushi/bstr and https://docs.rs/wtf8/latest/wtf8/ for working with non-unicode text

We are planning to add a C API to Taffy, but tbh I feel like C is not very good for this kind of modularised approach. You really want to be able to expose complex APIs with enforced type safety and this isn't possible with C.

As the author of bstr and also the regex implementation that bstr uses to implement word breaking, it is linear time.

NSFL: https://github.com/BurntSushi/bstr/blob/86947727666d7b21c97e...

OsStr uses WTF-8 on Windows, and just represents the raw underlying bytes on Unix.

Byte strings can be WTF-8. They can be anything. The problem is that there is no real way to (easily) get the underlying WTF-8 bytes of an OsStr on Windows. So there's no free conversion to and from byte strings.

I wrote more about this in the bstr docs (and don't miss the link to os_str_bytes): https://docs.rs/bstr/latest/bstr/#file-paths-and-os-strings

I'd be happy to answer more questions if you have them. :-) https://github.com/BurntSushi/bstr/discussions

Check out bstr, which does this exact thing for its BString and BStr types.

Currently slated for next Monday: https://github.com/BurntSushi/bstr/issues/40

This is just an FYI. I don't mean to say much to your overall point, although, as someone else who has spent a lot of time doing Unicode-y things, I do tend to agree with you. I had a very similar discussion a bit ago.[1]

Putting that aside, at least with respect to grapheme segmentation, it might be a little simpler than you think. But maybe only a little. The unicode-segmentation crate also does word segmentation, which is quite a bit more complicated than grapheme segmentation. For example, you can write a regex to parse graphemes without too much fuss[2]. (Compare that with the word segmentation regex, much to my chagrin.[3]) Once you build the regex, actually using it is basically as simple as running the regex.[4]

Sadly, not all regex engines will be able to parse that regex due to its use of somewhat obscure Unicode properties. But the Rust regex crate can. :-)

And of course, this somewhat shifts code size to heap size. So there's that too. But bottom line is, if you have a nice regex engine available to you, you can whip up a grapheme segmenter pretty quickly. And some regex engines even have grapheme segmentation built in via \X.

[1]: https://github.com/BurntSushi/aho-corasick/issues/72

[2]: https://github.com/BurntSushi/bstr/blob/e38e7a7ca986f9499b30...

[3]: https://github.com/BurntSushi/bstr/blob/e38e7a7ca986f9499b30...

[4]: https://github.com/BurntSushi/bstr/blob/e38e7a7ca986f9499b30...

This is a great idea. I realize the find implementation is not ideal and have considered bringing in an optional dependency to improve performance. I remembered bstr using two-way search, so I was wondering if depending on the full crate for searching would be worthwhile, but I see that changed. Thanks for the tip!

Fun little nit-pick that does not detract from your overall point: you can actually count graphemes with a regex and that's exactly what bstr does. :-)

1) No. I think semver is just fine for its intended purpose. I mean, I'm sure its spec could be improved in various ways, but its fundamental idea seems fine to me. I think it's just important to remember that semver is a means to an end, and not an end itself. It is a tool of communication most useful in a decentralized context.

2) No.

3) See: https://github.com/rust-lang/rust-semverver --- But also, this is only ever going to be a "best effort" sort of thing. Semver isn't just about method additions or deletions, but also behavior.

How does this compare to cargo-semverver?

Found this: https://github.com/rust-lang/rust-semverver but it doesn't seem to act on git log/diffs... just FYI.

Enter rust-semverver!

Rust type system on the other hand does not allow this. Traits are monotonic logic: adding trait-impls / most qualifiers does't influence already existing and compiling code (note: for code that doesn't rely on disambiguation to compile). There's rules that clarify this disambiguations and breaking/non-breaking changes according to the type system. There's SemVerVer to automatically verify those guidelines.

In my case it wasn't so bad and an easy fix was fast to write, but it got me thinking of how much of a problem this is for the wider ecosystem. Some searching showed me, that of course there is a tool rust-semverver to do exactly that. Sadly it errors on my system (or maybe im just using it wrong). Would've been interesting to see how often this actually happens on crates.io and how much of a problem this really is.

There's been an attempt at this for the Rust ecosystem: https://stackoverflow.com/questions/41185023/what-exactly-is...

There's also a library that attempts to automatically check sermver adherence of a crate: https://github.com/rust-lang/rust-semverver

And there has been quite a bit of effort into preventing semver requirements from fracturing the ecosystem. This revolves around the compiler working with multiple major versions of a single library: https://github.com/dtolnay/semver-trick

Turns out it already exists: https://github.com/rust-lang/rust-semverver