Regular Expressions 101

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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

/
/
i

Test String

Code Generator

Language

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"(?i)\[serviceOrderId:(?<oc_request_id>.[^]]*)\]").unwrap(); let string = "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 Transitional//EN\"><html><head> <meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\"></head><body><div><font face=\"Arial\" color=\"#000000\" size=\"2\">***** Reply to this email to append information to [[WO#17561]] *****<br><br>WO# 17561 was amended to include the following information:<br><br>Thank you for contacting us.<br><br><br>We have received your request and will respond within 2 business days.<br><br><br>Your request number is: REQ-20665.<br><br><br>If you would like to speak with a representative, please contact us at 1 855 242-4492 and reference your request number.<br><br><br>Our hours of operation are Monday to Friday, 8:00 am to 5:00 pm AST.<br><br><br>Thank you for your continued business with Bell Aliant.<br><br><br>Client Services<br>Bell Business Markets<br><br><br><br><br><br><br><br>Legal | Privacy | bell.ca <br><br>Corporate Secretary’s Office of Bell Canada, Bell TV, Bell Mobility, Bell Media and Bell Aliant<br>1 carrefour Alexander-Graham-Bell, Building A-7, Verdun, Quebec, H3E 3B3 <br><br><br><br>© Bell Canada, 2020. All rights reserved.<br><br><br><br><br>[serviceOrderId:bsd_REQ-20665] <br><br>Merci de nous avoir contacté.<br><br><br>Nous avons bien reçu votre demande et nous y réponderons dans 2 jours ouvrables.<br><br><br>Votre numéro de demande est : REQ-20665.<br><br><br>Si vous souhaitez parler à un conseiller, veuillez composer le 1 855 242-4492 et faire référence à votre numéro de demande.<br><br><br>Nos heures d'ouverture sont de 8 h à 17 h AST, du lundi au vendredi.<br><br><br>Merci de votre fidélité envers Bell Aliant.<br><br><br>Services clients<br>Bell Marché Affaires<br><br><br><br><br><br><br><br>Avis juridiques | Sécurité | bell.ca <br><br>Bureau du secrétaire de Bell Canada, Bell Télé, Bell Mobilité, Bell Média et Bell Aliant<br>1, carrefour Alexander-Graham-Bell, Aile A-7, Verdun (Québec) H3E 3B3 <br><br><br><br>© Bell Canada, 2020. Tous droits réservés.<br><br><br><br><br>[serviceOrderId:bsd_REQ-20665]<br><br></font></div><hr> <span style=\"font-size: 12px;\"><font color=\"blue\"><em><strong>External Email:</strong> Please use caution when opening links and attachments / </em></font></span><em> <span style=\"font-size: 12px;\"><font color=\"blue\"><strong>Courriel externe:</strong> Soyez prudent avec les liens et documents joints </font></span></em></body></html>"; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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/