Fast(er) regular expression engines in Ruby

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

60•davidsojevic•11mo ago

Comments

yxhuvud•11mo ago

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

gitroom•11mo ago

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

kayodelycaon•11mo 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•11mo 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•11mo 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•11mo 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.

Show HN: 30u30.fyi – Is your startup founder on Forbes' most fraudulent list?

Fedware: Government apps that spy harder than the apps they ban

Do your own writing

Learn Claude Code by doing, not reading

Android Developer Verification

Turning a MacBook into a touchscreen with $1 of hardware (2018)

How to turn anything into a router

Agents of Chaos

Bird brains (2023)

The stealthy startup that pitched brainless human clones

Cherri – programming language that compiles to an Apple Shortuct

Researchers find 3,500-year-old loom that reveals textile revolution

Seeing Like a Spreadsheet

Agentic AI and the next intelligence explosion

Roulette Computers: Hidden Devices That Predict Spins

OCR for construction documents does not work, we fixed it

William Blake, Remote by the Sea

A sea of sparks: Seeing radioactivity

Show HN: Coasts – Containerized Hosts for Agents

CodingFont: A game to help you pick a coding font

Recover Apple Keychain

In math, rigor is vital, but are digitized proofs taking it too far?

Build123d: A Python CAD programming library

IronGlass Brings Legendary Soviet Cinema Lenses to Mirrorless Cameras

Mathematical methods and human thought in the age of AI

I am definitely missing the pre-AI writing era

Take better notes, by hand

An NSFW filter for Marginalia search

Tickets Are Prompts

FTC action against Match and OkCupid for deceiving users, sharing personal data