rua VS regex

> While I find projects in those other languages to also have too many dependencies, it's no where near what happens in JS apps. I'm thinking of projects I've recently worked on in Rust, PHP, and Java.

My experience with these new languages is such that this feels a bit unfair. It's like insisting that a disaster with 1000 fatalities is "much worse" than one with "only". It's ... true ... I guess, but there's something uncomfortable about making the comparison. Something has gone badly wrong if the comparison even needs to happen in the first place.

What I'm getting at is that e.g. Rust has an enormous problem in this area. It's not uncommon for me to see Node projects with over a thousand transitive dependencies, but on the other hand, I very frequently see Rust projects with over a hundred. And the Node projects tend to be more complicated than the Rust ones; they do more.

Take the last Rust program I tried to use, tealdeer. [1] If you don't know, tldr is a project that provides alternative simplified man pages for commonly used programs that consist entirely of easy to understand examples for the program. [2] What a tldr client needs to do is simply to check a local cache for each lookup, and if necessary update the cache online. It's a trivial problem that can be, and has been! [3], solved in a few hundred lines of shell (if you're being extremely verbose). How many recursive dependencies would you guess tealdeer uses? Depends on how you count, of course, but as of today the answer is ~133 deduplicated dependencies! For a program that's a glorified wrapper around curl!

Or another Rust program I looked at recently, rua [4]. In Arch Linux, the AUR is a repository of user maintained scripts for building and installing software as native Arch packages. Official tools for the building and installing software already exist for Arch, but it is common for users to use a wrapper around these tools that makes fetching and updating the software from the AUR easier. It's a relatively simple task that (once again) can be done with shell scripts. rua is such a wrapper. As of today it uses 137 deduplicated dependencies!

These Rust programs are simple terminal tools to do tasks that are almost trivial in nature. And yet they require hundreds of constantly updating dependencies! The situation may well be better than what you'll find for Node, but it's undeniably disastrous compared to either simpler languages without a built in package manager (like C) or more complicated batteries-included languages where best practices continue to prevail (like Python).

[1] https://github.com/dbrgn/tealdeer

[2] https://tldr.sh/

[3] https://github.com/raylee/tldr-sh-client/blob/main/tldr

[4] https://github.com/vn971/rua

I gotta dig into rua too, seems cool!

Rua can do local patches (https://wiki.archlinux.org/title/AUR_helper#Comparison_tables)

https://github.com/vn971/rua#install-the-aur-way

The homepage has a benchmark that compares Zed's "insertion latency" to other editors, and this is the description:

> Open input.rs at the end of line 21 in rust-lang/regex. Type z 10 times, measure how long it takes for each z to display since hitting the z key.

Could someone clarify what that means? My interpretation of that was to go to https://github.com/rust-lang/regex/blob/master/regex-cli/arg... and start typing 'z' at the end of line 21, but that doesn't seem to make any sense. I guess that repo got refactored and those instructions are out of date?

We also used the avenue to sluggify the question title. We used regex to fish out and replace all occurrences of punctuation and symbol characters with an empty string and using the itertools crate, we joined the words back together into a single string, where each word is separated by a hyphen ("-").

Command-Line Rust taught me how to use crates like clap, assert_cmd, and regex. I felt lost before because I didn't know about Rust's ecosystem--which is arguably as important as the language itself. Also, looking up and comparing libraries is a tiring task! blessed.rs is nice but Command-Line Rust really saved me from analysis paralysis.

burntsushi actually regrets making regex replace return a Cow: https://github.com/rust-lang/regex/issues/676#issuecomment-6.... I’m glad it does, and wish it took an impl Into> there, for the reasons discussed in the issue, but burntsushi has a lot more experience of the practical outcomes of this. Just something more to think about.

I'm not familiar with the AoC problem. You might be able to. But RegexSet doesn't give you match offsets.

You can drop down to regex-automata, which does let you do multi-regex search and it will tell you which patterns match[1]. The docs have an example of a simple lexer[2]. But... that will only give you non-overlapping matches.

You can drop down to an even lower level of abstraction and get multi-pattern overlapping matches[3], but it's awkward. The comment there explains that I had initially tried to provide a higher level API for it, but was unsure of what the semantics should be. Getting the starting position in particular is a bit of a wrinkle.

[1]: https://docs.rs/regex-automata/latest/regex_automata/meta/in...

[2]: https://docs.rs/regex-automata/latest/regex_automata/meta/st...

[3]: https://github.com/rust-lang/regex/blob/837fd85e79fac2a4ea64...

It’s not quite that simple, but folks are working on it.

https://github.com/rust-lang/regex/issues/425#issuecomment-1...

https://github.com/helix-editor/helix/pull/211#issuecomment-...

Dependencies used: - regex - unicode_reader - rust decimal - tokio

https://www.cs.princeton.edu/courses/archive/fall19/cos226/l... and https://kean.blog/post/lets-build-regex are excellent introductions to implementing a (very) simplified regex engine: construct a nondetermistic finite state automaton for the regex, then perform a graph search on the resulting digraph; if the vertex corresponding to your end state is reachable, you have a match.

I think this exercise is valuable for anyone writing regexes to not only understand that there's less magic than one might think, but also to visualize a bunch of balls bouncing along an NFA - that bug you inevitably hit in production due to catastrophic backtracking now takes on a physical meaning!

Separately re: the OP, https://github.com/rust-lang/regex/issues/822 (and specifically BurntSushi's comment at the very end of the issue) adds really useful context to the paragraph in the OP about niche APIs: https://blog.burntsushi.net/regex-internals/#problem-request... - searching with multiple regexes simultaneously against a text is both incredibly complex and incredibly useful, and I can't wait to see what the community comes up with for this pattern!