Regular Expressions 101

Save & Share

  • Regex Version: ver. 2
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r"(?m)Json(?<json_output>[\s\S\d\D\w\W]*)").unwrap(); let string = "```json [ { \"Place\": { \"Name\": \"Les Catacombes de Paris\", \"Google_place_id\": \"ChIJVXealLU_xkcRja_At0z9AGY\", \"City\": \"Paris\", \"Region\": \"Île-de-France\", \"Country\": \"France\", \"Cultural_type\": \"Historical\", \"Facts\": { \"Historical_facts\": { \"FACT_TYPE\": \"Did you know ?\", \"FACTS\": [ \"Les Catacombes de Paris ont été créées à la fin du 18ème siècle pour résoudre le problème de surpeuplement des cimetières de la ville.\" ], \"INTERACTION\": [ \"Savez-vous pourquoi les catacombes ont été construites ?\" ], \"CATEGORY\": \"Historical_facts\" }, \"Architectural_facts\": { \"FACT_TYPE\": \"Fun fact\", \"FACTS\": [ \"Les catacombes sont faites d’anciens tunnels de carrières transformés pour stocker les ossements de plus de six millions de Parisiens.\" ], \"INTERACTION\": [ \"Combien de personnes pensez-vous que les catacombes peuvent contenir ?\" ], \"CATEGORY\": \"Architectural_facts\" }, \"Scientific_facts\": { \"FACT_TYPE\": \"Wow\", \"FACTS\": [ \"Les conditions dans les catacombes, qui sont fraîches et humides, permettent une bonne conservation des ossements.\" ], \"INTERACTION\": [ \"Que pensez-vous que l'humidité fait aux ossements ?\" ], \"CATEGORY\": \"Scientific_facts\" }, \"Mystery_legends_facts\": { \"FACT_TYPE\": \"Did you know ?\", \"FACTS\": [ \"Une légende urbaine raconte qu’il y a un cinéma secret dans les catacombes !\", \"Il paraîtrait que des groupes se réunissent ici pour regarder des films.\" ], \"INTERACTION\": [ \"Aimeriez-vous visiter un cinéma caché ?\", \"Quel genre de film pensez-vous qu’ils projettent là-bas ?\" ], \"CATEGORY\": \"Mystery_legends_facts\" } } } } ] ```"; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Rust, please visit: https://docs.rs/regex/latest/regex/