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.

Turtletoy

I failed to recreate the 1996 Space Jam website with Claude

Bag of words, have mercy on us

Damn Small Linux

Mechanical power generation using Earth's ambient radiation

Dollar-stores overcharge customers while promising low prices

The C++ standard for the F-35 Fighter Jet [video]

Google Titans architecture, helping AI have long-term memory

Work disincentives hit the near-poor hardest (2022)

Uninitialized garbage on ia64 can be deadly (2004)

An Interactive Guide to the Fourier Transform

Emacs Is My New Window Manager

Scala 3 slowed us down?

(2018) How I created a database of all interesting Rush Hour configurations

The Anatomy of a macOS App

How I block all online ads

CATL expects oceanic electric ships in 3 years

I wasted years of my life in crypto

Nested Learning: A new ML paradigm for continual learning

Build a DIY magnetometer with a couple of seasoning bottles

Show HN: Cdecl-dump - represent C declarations visually

A two-person method to simulate die rolls (2023)

The state of Schleswig-Holstein is consistently relying on open source

Minimum Viable Arduino Project: Aeropress Timer

Spinlocks vs. Mutexes: When to Spin and When to Sleep

Java Hello World, LLVM Edition

Estimates are difficult for developers and product owners

Socialist ends by market means: A history

Vibe Coding: Empowering and Imprisoning

Building a Toast Component