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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

$re = '/calypso:calypsoObject.{10,150}xsi:type="calypso:(\w{2,50})/m'; $str = '<calypso:calypsoDocument xmlns:datauploader="http://www.calypso.com/datauploader" xmlns:ftp="http://www.calypso.com/ftp" xmlns:liquidityrule="http://www.calypso.com/liquidityrule" xmlns:bloomberg="http://www.calypso.com/bloomberg" xmlns:liquiditycriteria="http://www.calypso.com/liquiditycriteria" xmlns:pricingscript="http://www.calypso.com/pricingscript" xmlns:am="http://www.calypso.com/am" xmlns:liquidityposition="http://www.calypso.com/liquidityposition" xmlns:scriptableOTC="http://www.calypso.com/scriptableOTC" xmlns:pricingsheet="http://www.calypso.com/pricingsheet" xmlns:matching="http://www.calypso.com/matching" xmlns:scheduler="http://www.calypso.com/scheduler" xmlns:ns20="http://www.calypso.com/HedgeAccounting" xmlns:liquidityreporting="http://www.calypso.com/liquidityreporting" xmlns:taskstation="http://www.calypso.com/taskstation" xmlns:kpiservice="http://www.calypso.com/kpiservice" xmlns:liquiditycore="http://www.calypso.com/liquiditycore" xmlns:calypso="http://www.calypso.com/xml" xmlns:assumption="http://www.calypso.com/assumption" xmlns:liquidityclassification="http://www.calypso.com/liquidityclassification" xmlns:collateral="http://www.calypso.com/collateral" xmlns:calculationserver="http://www.calypso.com/calculationserver" xmlns:bondexoticnote="http://www.calypso.com/bondexoticnote"><calypso:calypsoObject xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="calypso:FutureCommodity" version="14-0" action="SAVE"><calypso:identification><calypso:versionedIdentifier version="0" code="21866845" codifier="CPSLIVE"/></calypso:identification><calypso:definition><calypso:contract><calypso:type>com.calypso.tk.product.FutureContract</calypso:type><calypso:separator>#</calypso:separator><calypso:identifier code="USD#LME#LMEZinc" codifier="convention"/><calypso:calypsoBusinessKey><calypso:propertyName>currency</calypso:propertyName><calypso:propertyValue>USD</calypso:propertyValue></calypso:calypsoBusinessKey><calypso:calypsoBusinessKey><calypso:propertyName>exchange</calypso:propertyName><calypso:propertyValue>LME</calypso:propertyValue></calypso:calypsoBusinessKey><calypso:calypsoBusinessKey><calypso:propertyName>name</calypso:propertyName><calypso:propertyValue>LMEZinc</calypso:propertyValue></calypso:calypsoBusinessKey></calypso:contract><calypso:expirationDate>2023-10-30Z</calypso:expirationDate><calypso:firstDeliveryDate>2023-10-30Z</calypso:firstDeliveryDate><calypso:firstNotificationDate>2023-10-30Z</calypso:firstNotificationDate><calypso:lastDeliveryDate>2023-10-30Z</calypso:lastDeliveryDate><calypso:lastNotificationDate>2023-10-30Z</calypso:lastNotificationDate><calypso:tradingEndDate>2023-10-30Z</calypso:tradingEndDate><calypso:tradingStartDate>2023-10-30Z</calypso:tradingStartDate><calypso:ccpDate>2023-10-30Z</calypso:ccpDate></calypso:definition></calypso:calypsoObject></calypso:calypsoDocument>'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php