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

/
/
g

Test String

Code Generator

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"(%([^:]+):([^%]+)%)").unwrap(); let string = "<!DOCTYPE html>/ <html> <head> <meta http-equiv=\\\"Content-Type\\\" content=\\\"text/html; charset=utf-8\\\" /> <title>Testing the checkAndChangeToUrl-Function (Version 5)</title> <link rel=\\\"stylesheet\\\" type=\\\"text/css\\\" href=\\\"[__protocol__]://[__server__]:[__port__]/weblis-ext3/ext/resources/css/ext-all.css\\\" /> <script type=\\\"text/javascript\\\" src=\\\"[__protocol__]://[__server__]:[__port__]/weblis-ext3/ext/adapter/ext/ext-base-debug.js\\\"></script> <script type=\\\"text/javascript\\\" src=\\\"[__protocol__]://[__server__]:[__port__]/weblis-ext3/ext/ext-all-debug.js\\\"></script> <script type=\\\"text/javascript\\\" src=\\\"[__protocol__]://[__server__]:[__port__]/weblis-ext3/ext/locale/ext-lang-de.js\\\"></script> <script type=\\\"text/javascript\\\" src=\\\"[__protocol__]://[__server__]:[__port__]/weblis-resources/js/jquery/jquery-3.2.1.js\\\"></script> <script type=\\\"text/javascript\\\"> function checkAndChangeToUrl(url, maxRetries, waitTime, waitFunc, startFunc, successFunc, errorFunc) { console.log(\\\"ENTER checkAndChangeToUrl('\\\"+url+\\\"', \\\"+maxRetries+\\\", \\\"+waitTime+\\\")\\\"); var nRetry = 0; var checkUrl = function () { $.ajax({ url: url, context: document.body, crossDomain: true, error: function(jqXHR, textStatus, errorThrown) { console.error(textStatus + \\\"; \\\" + errorThrown); nRetry++; if (nRetry <= maxRetries) { waitFunc.call(jqXHR, jqXHR); console.log(\\\"Retry #\\\" + nRetry); var timeout = (nRetry == 0 ? 0 : waitTime); console.log(\\\"timeout = \\\" + timeout); setTimeout(checkUrl, timeout); if (nRetry === 1) { console.log(\\\"**** Try and open the target application ****\\\"); // PROBLEM: parent[.parent].handleExternalEvent() existiert nicht... startFunc.call(jqXHR, jqXHR); } } else { errorFunc.call(jqXHR, jqXHR); } return; }, success : function(data, textStatus, jqXHR) { console.log(\\\"Success!\\\"); successFunc.call(jqXHR, jqXHR); } }).done(function() { $( this ).addClass( \\\"done\\\" ); console.log(\\\"Done!\\\"); }); }; // Wir setzen das Ganze in Gang... checkUrl(); } function test_1(checkUrl, targetUrl, launchUrl) { //var url = \\\"%param:checkUrl%\\\"; //var url = \\\"http://localhost:8080/RechercheServlet/rest/forcont/fxLIS?DOKID=1&VID=1&OP=RECEIVE\\\"; //var url = \\\"http://localhost:8085/gn\\\"; console.log(\\\"VOR checkAndChangeToUrl('\\\"+checkUrl+\\\"', 2, 5000) ...\\\"); var ret = checkAndChangeToUrl(checkUrl, 2, 2000, function(jqXHR) { console.log(\\\"Waiting...\\\"); }, function(jqXHR) { console.log(\\\"Start application...\\\"); $.ajax({ url: %param:launchUrl%, //\\\"/opusp-rest/client-action/execute/local/GIS_Launch\\\", context: document.body, crossDomain: false, //true, -- SYNCHRONER AUFRUF - SCHWERE SÜNDE... headers: { 'Accept' : 'application/x-java-jnlp-file', /* application/jnlp */ 'Content-Description' : 'File Transfer', 'Content-Disposition' : 'attachment; filename=GIS_Launch.jnlp' }, error: function(jqXHR, textStatus, errorThrown) { console.error(\\\"Fehler bei Aktion GIS_Launch: \\\" + textStatus + \\\"; \\\" + errorThrown); return; }, success : function(data, textStatus, jqXHR) { console.log(\\\"GIS_Launch: Success! JNLP = '\\\" + data + \\\"'\\\"); } }).done(function() { $( this ).addClass( \\\"done\\\" ); console.log(\\\"GIS_Launch: Done!\\\"); }); }, function(jqXHR) { console.log(\\\"Success.\\\"); window.location.href = targetUrl; }, function(jqXHR) { console.log(\\\"Error: \\\" + jqXHR.statusText + \\\", jqXHR.state() = \\\" + jqXHR.state()); }); console.log(\\\"LEAVE test_1.\\\"); } function performTest_1() { test_1( \\\"[__checkUrl__]\\\", // Parameter: checkUrl, z.B. \\\"http://localhost:8080/RechercheServlet\\\" \\\"%param:targetUrl%\\\", // Parameter: targetUrl, z.B. \\\"http://localhost:8080/RechercheServlet/rest/forcont/fxLIS?DOKID=1&VID=1&OP=RECEIVE\\\" \\\"[__launchUrl__]\\\" // Parameter: launchUrl, z.B. \\\"/opusp-rest/client-action/execute/local/GIS_Launch\\\" ) } $.when($.ready).then(function() { performTest_1(); }); </script> </head> <body> <a id=\\\"test_1\\\" onclick=\\\"performTest_1();\\\"><button type=\\\"button\\\">Perform Test #1</button></a> </body> </html> "; // 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/