Regex ​

Regex Primer is great read.

I use regex101 every time I want write a new regex.

Pomsky is nice too.

Regular Expression Matching Can Be Simple And Fast & Regular Expression Matching: the Virtual Machine Approach are nice reads.

Notes ​

• .* = will select all occurrences
• A regex is useful for validating simple patterns and for finding patterns in text. For anything beyond that it’s almost certainly a terrible choice.

Code ​

Match if it has notes or twitter in input^(?=.*(?:notes|twitter)).*

Match all that don't have notes or twitter in input ^(?!._(?:notes|twitter))._

Links ​

• RegexLearn - Step by step, from zero to advanced. (HN) (Code)
• Learn regex the easy way
• Learn regex - Great reference.
• DebuggexBeta
• RegexOne - Learn Regular Expressions with simple, interactive exercises.
• Regular Expression in Python HOWTO - Good intro.
• Hyperscan - High-performance regular expression matching library.
• Oniguruma - Modern and flexible regular expressions library.
• Regex for Designers and UX Writers (2019)
• Regexes vs Combinatorial Parsing (2019)
• RegExr - Learn, Build & Test RegEx. (HN) (Code)
• regexgen - Generate regular expressions that match a set of strings. (Code)
• Regular Expressions - Computerphile (2020)
• Regex Tester - Visual regex tester.
• I hate Regex - Regex cheat sheet (HN) (Code)
• grex - Command-line tool and library for generating regular expressions from user-provided test cases.
• Regular Expressions for Regular Folk (HN)
• regHEX - Magical sticky regex-based parser generator.
• tiny-regex-c - Small portable regex in C.
• Structural Regular Expressions - Rob Pike (Lobsters)
• Regexes vs Combinatorial Parsing (2020) (HN)
• Regex Crossword
• RegEx Crossword 2
• libfsm - DFA regular expression library & friends.
• Python re(gex) book - Learn Python Regular Expressions step by step from beginner to advanced levels with hundreds of examples and exercises. (Code)
• JavaScript RegExp - Example based guide to mastering JavaScript regexp. (Article)
• Compile time regular expressions
• A Visual Guide to Regular Expression (2020)
• Emulating regexp lookarounds in GNU sed (2020)
• Try Regex - Interactive regex tutorial. (Code)
• Three Great Videos About Regex Derivatives (2020)
• Super Expressive - Zero-dependency JavaScript library for building regular expressions in (almost) natural language. (HN)
• Stephen Kleene's 1951 Paper Where He Introduces Regular Expressions
• Implementing Regular Expressions (Lobsters)
• Avoid RegEx (2021)
• RegEx Pal - Test your regular expressions quickly.
• Regular expression compilation visualized (HN)
• regex101 - Build, test, and debug regex. (Issues)
• igrepper - Interactive grepping using ncurses and rust.
• Some useful regular expressions for programmers (2021) (HN)
• Bling Fire - Lightning fast Finite State machine and REgular expression manipulation library.
• Let’s Build a Regex Engine (2019) (HN)
• GNU BRE/ERE cheatsheet and differences between grep, sed and awk (2021)
• The Best Regex Trick (2014) (HN)
• The Regular Expression Edition (2021) - On code, early neural networks, and once discredited AI pioneers.
• REXS - Language for writing regular expressions.
• Regex cheatsheet (Code)
• Regex Legends: The People Behind the Magic
• Regexly - WYSIWYG Regex playground for those who JavaScript. (Code)
• Orchestra - Visual language that compiles into RegExp.
• UltimateRegexResource - Ultimate collection of regex syntax and resources.
• Regex Generator - Generate regular expressions from sample texts. (Code)
• Regex-like domain-specific language for pattern matching syntax trees
• rxe - Literate and composable regular expressions.
• Recognize Regex Easily (2020)
• Regex literals optimization (2020)
• A DFA for submatches extraction (2020)
• regex-cache - Memoize the results of a call to the RegExp constructor, avoiding repetitious runtime compilation.
• tree-sitter-regex - Regex grammar for tree-sitter.
• rr4r - Rust regex for R.
• Regulex - JavaScript Regular Expression Parser & Visualizer. (Code)
• Regexes are Cool and Good (2022) (Lobsters)
• RegEx Library - Curated list of useful regular expressions for different programming languages.
• A Regular Expression Matcher
• Melody - Language that compiles to regular expressions and aims to be more easily readable and maintainable. (HN) (Reddit)
• Alternative Regex Syntax (Lobsters)
• Python support for regular expressions (2022)
• A regular expression to check for prime numbers (2007) (HN)
• Pomsky - New, portable, regular expression language. (Reddit) (Web) (HN) (HN) (Lobsters)
• rare - Real time regex-extraction and aggregation into common formats such as histograms, bar graphs, numerical summaries, tables, and more.
• Regex Vis - Regex visualizer & editor. (Code) (HN)
• I-Regexp - Interoperable Regexp Format.
• compose-regexp.js - Build and compose maintainable regular expressions in JavaScript.
• flexlint - Flexible linter with rules defined by regular expression.
• Animating Regular Expressions With Python and Graphviz (2022)
• Web tool to evaluate rust regular expressions (Code)
• super-regex - Make a regular expression time out if it takes too long to execute.
• patterns-finder - Simple, Fast, Powerful and Easily extensible python package for extracting patterns from text, with over than 60 predefined Regular Expressions.
• Utilties for the Developer. Regex, HTTP echo. Diffing (Code)
• Swift Regex - Online tool to learn, build and test Swift Regex Regex and Regex Builder. (Code)
• regexparam - Tiny (394B) utility that converts route patterns into RegExp.
• AutoRegex - Convert from English to RegEx with Natural Language Processing. (HN)
• magic-regexp - Compiled-away, type-safe, readable RegExp alternative.
• PRegEx - Programmable Regular Expressions.
• Rex - JS Library for writing complex RegExps with help of auto completion.
• regexp-tree - Regular expressions processor in JavaScript.
• On the Intersection of Context-Free and Regular Languages (2022)
• The Typing of the RegEX (HN)
• How Do Regular Expressions Really Work? (2020)
• Ken Thompson's NFA regex patent (HN)
• What if regular exercise is the best cognitive exercise? (2022) (HN)
• How Regexes Work (HN)
• qgrep - Fast regular expression grep for source code with incremental index updates.
• A Regex Primer (2022)
• nvim-regexplainer - Describe the regular expression under the cursor.
• Regular Expression Matching Can Be Simple And Fast (2007)
• Regular Expression Matching: the Virtual Machine Approach (2009)
• universalmutator - Regexp based tool for mutating generic source code across numerous languages.
• Regular Expression Matching with a Trigram Index (2012) (HN)
• Writing The Perfect RGB Regex And Failing (2023)
• Regex Library in Rust from Scratch (Finite-State Machines) (2021)
• Regex Derivatives (Brzozowski Derivatives)
• ChatGPT is a regex god
• Regex.ai - AI-powered regular expression generator. (HN)
• Learn how regular expressions work under the hood
• Regexper - Regular Expression Visualization. (Code)
• Regex Engine Internals as a Library (2023) (HN)
• rebar - Biased barometer for gauging the relative speed of some regex engines on a curated set of tasks.
• Regex Isn't Hard (2023) (Lobsters)
• How a Regex Engine Works Internally
• Calculate the difference and intersection of any two regexes (HN)
• Antimirov - Algebraic manipulation of regular expressions.