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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"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" test_str = ("date_modified21-DECEMBER-2020 12:25 PMinternal_id313017task2nd Year Annual\n" "billing pricing -34515priorityMediumstatusCompletedtask_statusAllocatedcreated\n" "Bernadine PereraassignedBernadine Pereradate_created21-DECEMBER-2020 12:25 PM\n" "date_started21-DECEMBER-2020date_due21-DECEMBER-2020date_completed\n" "21-DECEMBER-2020bunitOperationstask_vendorSplunktask_categoryOthercustomer\n" "cust_namecust_territorycontacttime_datetime_durationcommentopportunityopp_status\n" "opp_engineertransaction yeg_idRecent Changes\n\n" "DateSet byContextTypeFieldOld ValueNew Value21-DECEMBER-2020 12:25 PMBernadine\n" "PereraUISetStart Date21-DECEMBER-2020 12:00 Utc21-DECEMBER-2020 12:25 PM\n" "Bernadine PereraUISetOwnerBernadine Perera21-DECEMBER-2020 12:25 PMBernadine\n" "PereraUISetAssignedBernadine Perera21-DECEMBER-2020 12:25 PMBernadine PereraUI\n" "SetBusiness UnitOperations21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask\n" "CategoryOther21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask StateAllocated\n" "21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask VendorSplunk21-DECEMBER-2020\n" "12:25 PMBernadine PereraUICreateRecordTASK313017You requested to receive an\n" "email alert for this record. Click here to modify your email alerts\n" "[https://55349.app.netsuite.com/app/center/userprefs.nl?sc=-29&selectedtab=alerts]") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html