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

/
/
gi

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?i)(href|src|source|retinaSource|data)=(["|'][^"']*assets[^"']*\.\w{1,5})(\?[^"']*)?["|']`) var str = `<a href="javascript://" class="btn btn-continue-operation disabled"> <span>Continuar</span> </a> <a href='javascript://" class="btn btn-continue-operation disabled'> <span>Continuar</span> </a> <ul class="footer-legal l-adjacent-list"> <li><a href="#external-content//genoma_transactional/cms_files/corporativo/seguridad-internet/index_transaccional.html" class="footer-legal-element clr-gray.html">{security}</a></li> <li><a href='#external-content//genoma_transactional/cms_files/corporativo/sobre-ing/condiciones-servicio-tarifa_transaccional.html' class="footer-legal-element clr-gray">{link-legal-info-footer}</a></li> </ul> <link type="text/css" href=" assets/custom-css /infobolsa .css" rel="stylesheet" media="all" charset="utf-8"> <div class="fingerprint-views-storage-content-img txt-c"> {>pp-image imageId="fingerprint-activation" altText="fingerprint-activation" source="assets/images/fingerprint-activation.png" retinaSource="assets/images/retina/fingerprint-activation@2x.png"/} </div> <img src="modules/cc-menu/assets/images/logo_cc.svg" alt="Components catalog"> <img src="assets/images/twyp_cash_circle.svg?query=34"> <img src="assets/ircle.svg?hgt=76"> {>pp-image imageId="budgets-tutorial-client-step3" altText="budget-tutorial-step3" source="components/budgets-tutorial/ASSETS/images/budgets-tutorial-client-step3.png" {>pp-image imageId="budgets-tutorial-client-step3" altText="budget-tutorial-step3" source="components/budgets-tutorial/ASSETS/images/budgets-tutorial-client-step3.png" {>pp-image source="assets/images/svg/logoING.svg"/} <div data-selector="logo-ing" class="padding-top-sm padding-left-sm pull-left"> <img id="logo" src="assets/images/svg/logoING.svg" class="img-svg svg-header-logo login-header"> </div> <audio data-selector="customer-connected-audio"> <source src="modules/remote-advisor-agent/assets/audio/incomingCall.mp3" type="audio/mp3"/> </audio> <div class="col9"> <div class="declaration-image-div">{>pp-svg-image:no-products-other-bank imageId="declaration-image" source="./assets/images/life-insurance-contract/cuestionario_riesgos.svg"/}</div> <p class="h5 clr-dark-gray lic-declaration-remark">{lic-risk-declaration-remark|s}</p> </div> <div data-region-id="login-dnie-image" class="login-dnie-image"><img src="assets/images/dni-logo.png"/></div>` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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 Golang, please visit: https://golang.org/pkg/regexp/