Fast(er) regular expression engines in Ruby

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

60•davidsojevic•1y ago

Comments

yxhuvud•12mo ago

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

gitroom•12mo ago

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

kayodelycaon•12mo 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•12mo 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•12mo 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•12mo 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.

Ask.com has closed

Ti-84 Evo

Job Postings for Software Engineers Are Rapidly Rising

Artemis II Photo Timeline

New research suggests people can communicate and practice skills while dreaming

LFM2-24B-A2B: Scaling Up the LFM2 Architecture

K3k: Kubernetes in Kubernetes

CollectWise (YC F24) Is Hiring

To Restore an Island Paradise, Add Fungi

I built the Playwright for desktop apps. 80% token savings

I'm Peter Roberts, immigration attorney who does work for YC and startups. AMA

Direct electrochemical black coffee quality appraisal using cyclic voltammetry

Lib0xc: A set of C standard library-adjacent APIs for safer systems programming

Sourcefeed – a pop-up RSS service

Ask HN: Who is hiring? (May 2026)

Eka’s robotic claw feels like we're approaching a ChatGPT moment

The smelly baby problem

Show HN: WhatCable, a tiny menu bar app for inspecting USB-C cables

A Report on Burnout in Open Source Software Communities (2025) [pdf]

Whohas – Command-line utility for cross-distro, cross-repository package search

Chasing a SharedKey signature mismatch: fix azurerm_storage_table_entity

Apocalypse Early Warning System

Whimsical Animations Course Open House

Create an MP4 video of a web page scrolling at a steady speed

City Learns Flock Accessed Cameras in Children's Gymnastics Room as a Sales Demo

Tvheadend: Self-Hosted IPTV Server

The gay jailbreak technique (2025)

Show HN: AI CAD Harness

Understand Anything

Ask HN: Who wants to be hired? (May 2026)