Fast(er) regular expression engines in Ruby

https://serpapi.com/blog/faster-regular-expression-engines-in-ruby/

60•davidsojevic•9mo ago

Comments

yxhuvud•9mo ago

Eww, pretending to support utf8 matchers while not supporting them at all was not pretty to see.

gitroom•9mo ago

Honestly that part bugs me, fake support is worse than no support imo

kayodelycaon•9mo ago

> Another nuance was found in ruby, which cannot scan the haystack with invalid UTF-8 byte sequences.

This is extremely basic ruby: UTF-8 encoded strings must be valid UTF-8. This is not unique to ruby. If I recall correctly, python 3 does the same thing.

    2.7.1 :001 > haystack = "\xfc\xa1\xa1\xa1\xa1\xa1abc"
    2.7.1 :003 > haystack.force_encoding "ASCII-8BIT"
    => "\xFC\xA1\xA1\xA1\xA1\xA1abc" 
    2.7.1 :004 > haystack.scan(/.+/)
    => ["\xFC\xA1\xA1\xA1\xA1\xA1abc"]

This person is a senior engineer on their Team page. All they had to do was google "ArgumentError: invalid byte sequence in UTF-8". Or ask a coworker... the company has Ruby on Rails applications. headdesk

burntsushi•9mo ago

The nuance is specifically relevant here because neither of the other two regex engines benchmarked have this requirement. It's doubly relevant because that means running a regex search doesn't require a UTF-8 validation step, and is therefore likely beneficial from a perf perspective, dependening on the workload.

kayodelycaon•9mo ago

That’s a good point. I hadn’t considered it because I’ve hit the validation error long before getting to search. It is possible to avoid string operations with careful coding prior to the search.

Edit: After a little testing, the strings can be read from and written to files without triggering validation. Presumably this applies to sockets as well.

DmitryOlshansky•9mo ago

I wonder how std.regex of dlang would fare in such test. Sadly due to a tiny bit of D’s GC use it’s hard to provide as a library for other languages. If there is an interest I might take it through the tests.

Halt and Catch Fire: TV's Best Drama You've Probably Never Heard Of (2021)

Claude Sonnet 4.6

Thank HN: You helped save 33k lives

Thousands of CEOs just admitted AI had no impact on employment or productivity

BarraCUDA Open-source CUDA compiler targeting AMD GPUs

Show HN: AsteroidOS 2.0 – Nobody asked, we shipped anyway

Minimal x86 Kernel Zig

Gentoo on Codeberg

Using go fix to modernize Go code

So you want to build a tunnel

Google Public CA is down

Async/Await on the GPU

Reverse Engineering Sid Meier's Railroad Tycoon for DOS from 1990

I swear the UFO is coming any minute

Assistant to the Regional Manager

Is Show HN dead? No, but it's drowning

Show HN: I wrote a technical history book on Lisp

It's not just you, YouTube is partially down in outage

I converted 2D conventional flight tracking into 3D

Structured AI (YC F25) Is Hiring

Show HN: Pg-typesafe – Strongly typed queries for PostgreSQL and TypeScript

'My Words Are Like an Uncontrollable Dog': On Life with Nonfluent Aphasia

Physicists Make Electrons Flow Like Water

I Use Obsidian

HackMyClaw

Use Microsoft Office Shortcuts in Libre Office

Advice, not control: the role of Remote Assistance in Waymo's operations

Create bootable ISO image files which are compatible with the Amiga CD32

A Brief History of Xenopus

Tesla Sales Down 55% UK, 58% Spain, 59% Germany, 81% Netherlands, 93% Norway