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

/
/
gm

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"(?m)date_modified(?<date_modified>(?:.*?\n?)*?)internal_id(?<internal_id>(?:.*?\n?)*?)task(?<task>(?:.*?\n?)*?)priority(?<priority>(?:.*?\n?)*?)status(?<status>(?:.*?\n?)*?)task_status(?<task_status>(?:.*?\n?)*?)created(?<created>(?:.*?\n?)*?)assigned(?<assigned>(?:.*?\n?)*?)date_created(?<date_created>(?:.*?\n?)*?)date_started(?<date_started>(?:.*?\n?)*?)date_due(?<date_due>(?:.*?\n?)*?)date_completed(?<date_completed>(?:.*?\n?)*?)bunit(?<bunit>(?:.*?\n?)*?)task_vendor(?<task_vendor>(?:.*?\n?)*?)task_category(?<task_category>(?:.*?\n?)*?)customer(?<customer>(?:.*?\n?)*?)cust_name(?<cust_name>(?:.*?\n?)*?)cust_territory(?<cust_territory>(?:.*?\n?)*?)contact(?<contact>(?:.*?\n?)*?)time_date(?<time_date>(?:.*?\n?)*?)time_duration(?<time_duration>(?:.*?\n?)*?)comment(?<comment>(?:.*?\n?)*?)opportunity(?<opportunity>(?:.*?\n?)*?)opp_status(?<opp_status>(?:.*?\n?)*?)opp_engineer(?<opp_engineer>(?:.*?\n?)*?)transaction(?<transaction>(?:.*?\n?)*?)yeg_id(?<yeg_id>(?:.*?\n?)*?)Recent Changes").unwrap(); let string = "date_modified21-DECEMBER-2020 12:25 PMinternal_id313017task2nd Year Annual billing pricing -34515priorityMediumstatusCompletedtask_statusAllocatedcreated Bernadine PereraassignedBernadine Pereradate_created21-DECEMBER-2020 12:25 PM date_started21-DECEMBER-2020date_due21-DECEMBER-2020date_completed 21-DECEMBER-2020bunitOperationstask_vendorSplunktask_categoryOthercustomer cust_namecust_territorycontacttime_datetime_durationcommentopportunityopp_status opp_engineertransaction yeg_idRecent Changes DateSet byContextTypeFieldOld ValueNew Value21-DECEMBER-2020 12:25 PMBernadine PereraUISetStart Date21-DECEMBER-2020 12:00 Utc21-DECEMBER-2020 12:25 PM Bernadine PereraUISetOwnerBernadine Perera21-DECEMBER-2020 12:25 PMBernadine PereraUISetAssignedBernadine Perera21-DECEMBER-2020 12:25 PMBernadine PereraUI SetBusiness UnitOperations21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask CategoryOther21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask StateAllocated 21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask VendorSplunk21-DECEMBER-2020 12:25 PMBernadine PereraUICreateRecordTASK313017You requested to receive an email alert for this record. Click here to modify your email alerts [https://55349.app.netsuite.com/app/center/userprefs.nl?sc=-29&selectedtab=alerts]"; // 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/