Regular Expressions 101

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Community Patterns

1

Words that are only sequences of Chemical Element Symbols, allowing smushes

PCRE2 (PHP >=7.3)
This will match only words that include chemical elements: H + Og + W + Ar + Ts but not Eton. It allows internal overlap: LaG = La + Ag, and allows the first letter or last letter to be the end/start of a symbol to allow chaining. You can easily remove the various pieces, though. A single-line (non...
Submitted by mrflip - 7 hours ago (Last modified 6 hours ago)
1

Validate a comma separated list of IPv4 addresses, CIDRs, or IPv4 Ranges like 1.1.1.1-1.1.1.10

Golang
Simple Regex to *validate * (no extraction!) an IPv4 Range which can be a comma separated mixture of IPv4 addresses IPv4 CIDRs IPv4 Ranges like 1.1.1.1-1.1.1.10 Examples : ...
Submitted by alucab - 5 days ago
1

test

ECMAScript (JavaScript)
testing
Submitted by madgregory - 6 days ago
1

MobaXterm SSH session dump data

PCRE2 (PHP >=7.3)
Below regex pattern help to extract needful information from Portable export of SSH sessions. Although not complete, can help data extraction from export file.
Submitted by anonymous - 9 days ago
1

Russian phone number (российские номера телефонов)

PCRE2 (PHP >=7.3)
A regular expression for searching for phone numbers in the Russian format, taking into account different ways of writing the number, including spaces, brackets and dashes. Регулярное выражение для поиска номеров телефонов Российского формата. Учитывает написание номера через пробел, скобки, тире и ...
Submitted by https://t.me/ds_ivanov - 9 days ago
1

Factorization: Zero, Unit, Primes, or Composite?

.NET 7.0 (C#)
Description Inspects lines that contain only a character, let's say c, repeated n times. The name of the matching groups will tell you if n is 0, the unit 1, a prime number, or a composite number. Alternative ...
Submitted by kevinhp - 9 days ago
1

semver2.0.0_franenguix

Python
Given a version number MAJOR.MINOR.PATCH, increment the: MAJOR version when you make incompatible API changes. MINOR version when you add functionality in a backward compatible manner. PATCH version when you make backward compatible bug fixes. A pre-release version MAY be denoted by appending a hyp...
Submitted by FranEnguix - 9 days ago (Last modified 9 days ago)
1

Match the web URL

PCRE2 (PHP >=7.3)
Match the web URL, like https://xxx.com or xxx.com, not matching the email or the ip address
Submitted by Hughie - 10 days ago
1

96 Bit Decryption

PCRE2 (PHP >=7.3)
Part 2 of my post.
Submitted by Dave Cummins - 11 days ago
1

96 Bit Encryption

PCRE2 (PHP >=7.3)
96 Bit encryption by using a library. Possible to extend this beyond 96 if you have the time! Look at my other post to see how to decrypt. Based on using a library of values.
Submitted by Dave Cummins - 11 days ago
1

Chemical equation one side

PCRE2 (PHP >=7.3)
Matches one side of a chemical equation. So for ` 2HCl + 2Na → 2NaCl + H2 ` it would match each side individually with one newline between each 2HCl + 2Na and 2NaCl + H2
Submitted by viktorashi - 13 days ago
1

Antimony CRN definition

PCRE2 (PHP >=7.3)
Describes how the first few lines of an Antimony (for Tellurium) CRN definition should look like
Submitted by viktorashi - 13 days ago
1

GPT multiline equations match

Python
substitutes \[...\] with $$...$$
Submitted by MyAiTree - 14 days ago (Last modified 7 days ago)
1

ChatGPT Equations to MD equations

Python
Substitute the oneliner GPT equations \(..\) to tex like i.e. $..$
Submitted by MyAITree - 14 days ago
1

Trim Slashes

PCRE2 (PHP >=7.3)
Remove leading and trailing slashes
Submitted by anonymous - 20 days ago
1

SELECT

PCRE2 (PHP >=7.3)
/^select\s+(?.+?)\s+from\s+(?\S+)\s*(?:where\s+(?[\d\w= ><!]+))?;?$/gmi
Submitted by anonymous - 22 days ago
1

regex for mobile numbers

PCRE2 (PHP >=7.3)
regex to validate mobile numbers all over the world
Submitted by anonymous - 23 days ago
1

Credit Cart Prediction & Validation

ECMAScript (JavaScript)
Credit Card Carrier Prediction This regex is specifically designed to predict from the first few characters which carrier type the credit card number is.
Submitted by anonymous - 25 days ago (Last modified 23 days ago)
1

Match a^nb^n

Python
Matches some number of a's followed by the same number of b's, usually written as a^nb^n for all natural numbers n. For regular expressions as formally defined in formal language theory, this is impossible, but modern day regex engines can do far more than match just regular languages. Note that eve...
Submitted by FieryIceStickie - a month ago
1

SVG viewbox parser

Python
for finding and extracting numbers from the viewbox attribute. see also my generalized SVG number regex. v2: added support for scientific notation
Submitted by riedler - a month ago (Last modified 22 days ago)
123...900

Community Library Entry

1

Regular Expression
PCRE2 (PHP >=7.3)

/
^ # Uncomment to allow prefix continuation (second letter of a dangling match) # ([abcdefghiklmnoprstuvy\ ])? ( \ |(?: # Single-letter elements [BCFHIKNOPSUVWY] ) |(?: # Two-letter elements. (?:A[cglmrstu])|(?:B[aehikr])|(?:C[adeflmnorsu])|(?:D[bsy]) | (?:E[rsu])|(?:F[elmr])|(?:G[ade])|(?:H[efgos])|(?:I[nr]) | (?:K[r])|(?:L[airuv])|(?:M[cdgnot])|(?:N[abdehiop]) | (?:O[gs])|(?:P[abdmortu])|(?:R[abefghnu])|(?:S[bcegimnr]) | (?:T[abcehilms])|(?:X[e])|(?:Yb)|(?:Z[nr]) ) |(?: # Smushed trigrams. No need to go past trigrams because two twos make four (?:A(?:ga|gd|ge|la|lr|md|mg|mt|ra|re|rg|ta|te|tl|tm)) |(?:E(?:ra|re|rg)) |(?:G(?:ag|al|am|ar|at|er)) |(?:L(?:ag|al|am|ar|at|ra|re|rg)) |(?:M(?:ga|gd|ge|ta|te|tl|tm)) |(?:R(?:ag|al|am|ar|at|er|ga|gd|ge)) |(?:T(?:ag|al|am|ar|at|er|la|lr|md|mg|mt)) |(?:X(?:er)) |(?:Z(?:ra|re|rg)) ) # repeated any number of times )+ # Uncomment to allow last letter if it's a potential first letter of the next word # ([ADEGLMRTXZ]\ *)? $
/
gimx
Open regex in editor

Description

This will match only words that include chemical elements: H + Og + W + Ar + Ts but not Eton. It allows internal overlap: LaG = La + Ag, and allows the first letter or last letter to be the end/start of a symbol to allow chaining. You can easily remove the various pieces, though. A single-line (non-"extended") regex is at the bottom of the test string

Submitted by mrflip - 7 hours ago (Last modified 6 hours ago)