Fast(er) regular expression engines in Ruby

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

60•davidsojevic•7mo ago

Comments

yxhuvud•7mo ago

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

gitroom•7mo ago

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

kayodelycaon•7mo 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•7mo 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•7mo 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•7mo 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.

Size of Life

Getting a Gemini API key is an exercise in frustration

Patterns.dev

Australia begins enforcing world-first teen social media ban

Auto-grading decade-old Hacker News discussions with hindsight

Incomplete list of mistakes in the design of CSS

Booting Linux in QEMU and Writing PID 1 in Go to Illustrate Kernel as Program

Fossils reveal anacondas have been giants for over 12 million years

Super Mario 64 for the PS1

3D-printed carotid artery-on-chips for personalized thrombosis investigation

How Google Maps allocates survival across London's restaurants

VCMI: An open-source engine for Heroes III

Show HN: Wirebrowser – A JavaScript debugger with breakpoint-driven heap search

Rubio stages font coup: Times New Roman ousts Calibri

Qwen3-Omni-Flash-2025-12-01：a next-generation native multimodal large model

When would you ever want bubblesort? (2023)

Show HN: Automated license plate reader coverage in the USA

Common Lisp, ASDF, and Quicklisp: packaging explained

Python Workers redux: fast cold starts, packages, and a uv-first workflow

Scientists create ultra fast memory using light

Terrain Diffusion: A Diffusion-Based Successor to Perlin Noise

Valve: HDMI Forum Continues to Block HDMI 2.1 for Linux

Is it a bubble?

Gundam is just the same as Jane Austen but happens to include giant mech suits

The future of Terraform CDK

Launch HN: InspectMind (YC W24) – AI agent for reviewing construction drawings

Golang's big miss on memory arenas

Yadea is coming to the Western market

RoboCrop: Teaching robots how to pick tomatoes

9 Mothers (YC X26) Is Hiring