slev
Show HN: I made native JavaScript regexes competitive with the best re flavors
https://github.com/slevithan/regex
I'm a longtime regex superfan, having coauthored O'Reilly Media's Regular Expressions Cookbook and creating/contributing to a variety of open source regex tools. I also love JavaScript, but historically its regexes have been underpowered compared to other modern regex flavors. So I recently created a lightweight library that upgrades native JS regexes with key features that, when combined with...
Re:Show HN: Awesome Regex – Best tools/tuts/libs/etc. for all major re...
on Wednesday May 08, 2024 @11:30AM (#40299224)
Ack! Thanks for the info/link. I've now hidden this post.
Show HN: Awesome Regex – Best tools/tuts/libs/etc. for all major regex flavors
https://github.com/slevithan/awesome-regex
I created a curated and opinionated list of the best regular expression tools, tutorials, libraries, and many other resources. It covers all major regex flavors, and currently includes especially deep coverage of regular expressions in JavaScript (including a concise history of all regex features added to JavaScript in ES6 through ES2024, plus active proposals for the future).
Re:ParseUri: A mighty but tiny URI parser (less than 50 lines to suppo...
on Wednesday April 10, 2024 @11:34AM (#39991901)
I created parseUri v1 17 years ago, but never hosted it on GitHub/npm because it's older than both of those tools. Nevertheless, it’s been used very widely due to it being tiny and predating JavaScript’s built-in `URL` constructor. After this short gap, I just released v2 with a ton of improvements: https://github.com/slevithan/parseuri
It’s still tiny (nothing similar comes close, even with libraries that support far fewer URI parts, types, and edge cases), and it includes several advantages over JavaScript's built-in `URL` constructor:
* parseUri gives you many additional properties (authority, userinfo, subdomain, domain, tld, resource, directory, filename, suffix) that aren’t available from `URL`.
* `URL` throws e.g. if not given a protocol, and in many other cases of valid (but not supported) and invalid URIs. parseUri makes a best case effort even with partial or invalid URIs and is extremely good with edge cases.
* `URL`’s rules don’t allow correctly handling many non-web protocols. For example, `URL` doesn’t throw on any of 'git://localhost:1234', 'ssh://[email protected]', or 't2ab:///path/entry', but it also doesn’t get their details correct since it treats everything after : up to ? or # as part of the pathname.
* parseUri includes a “friendly” parsing mode (in addition to its default mode) that handles human-friendly URLs like 'example.com/index.html' as expected.
* parseUri includes partial/extensible support for second-level domains like in '//example.co.uk'.
So although it’s needed less often these days because of the built-in `URL`, if `URL` is ever not enough for your needs, this is an extremely accurate, flexible, and lightweight option.
The parseUri demo page lets you easily test results and compare them with `URL`: https://slevithan.github.io/parseuri/demo/
ParseUri: A mighty but tiny URI parser (less than 50 lines to support all URIs)
Re:Regex Legends: The People Behind the Magic
on Monday July 19, 2021 @10:00PM (#27889366)
These days people study regular languages as part of the Chomsky hierarchy, but back when regular expressions were introduced into computing the term referred to Kleene’s regular expressions.