Regular Expressions 101

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  • Unit Tests (7)

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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

Substitution

Processing...

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)<(script|style)((?:(?!src|nonce).)*?)>`) var str = `<!DOCTYPE html> <html class="no-js" lang="en-US"> <script>window._wpemojiSettings = {"baseUrl":"https:\/\/s.w.org\/images\/core\/emoji\/13.0.0\/72x72\/","ext":".png","svgUrl":"https:\/\/s.w.org\/images\/core\/emoji\/13.0.0\/svg\/","svgExt":".svg","source":{"wpemoji":"https:\/\/localhost:32810\/wp-includes\/js\/wp-emoji.js?ver=5.6-alpha-48683-src","twemoji":"https:\/\/localhost:32810\/wp-includes\/js\/twemoji.js?ver=5.6-alpha-48683-src"}}; } );</script> <style>img.emoji {padding: 0 !important;}</style> <style id='twentytwenty-style-inline-css'>.color-accent{ color: #cd2653; }</style> <script src='https://localhost:32810/wp-content/themes/twentytwenty/assets/js/index.js?ver=1.5' id='twentytwenty-js-js' async></script> <script>document.documentElement.className = document.documentElement.className.replace( 'no-js', 'js' );</script> <style>.recentcomments a{display:inline !important;padding:0 !important;margin:0 !important;}</style> <style media="print">#wpadminbar { display:none; }</style> <style media="screen">html { margin-top: 32px !important; }</style> </head> <body> <script test>(function() {var request; b[c] = b[c].replace( rcs, ' ' );}());</script> <script src='https://localhost:32810/wp-includes/js/hoverintent-js.min.js?ver=2.2.1' id='hoverintent-js-js'></script> <script src='https://localhost:32810/wp-includes/js/admin-bar.js?ver=5.6-alpha-48683-src' id='admin-bar-js'></script> <script src='https://localhost:32810/wp-includes/js/wp-embed.js?ver=5.6-alpha-48683-src' id='wp-embed-js'></script> <script test>var t, e = location.hash.substring(1);</script> </body> </html>` var substitution = "<$1 nonce="test"$2>" fmt.Println(re.ReplaceAllString(str, 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 Golang, please visit: https://golang.org/pkg/regexp/