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

/
/
gs

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"(?s)\[\@if(not)?:([a-zA-Z0-9]+)(?:=(.*?))?\].*?\[\@endif:\2\]").unwrap(); let string = "<!-- <h1>[!WLANSettings]</h1> --> [@if:examplevar=notgiven]this text won't show[@endif:examplevar] [@if:wlanena] [@if:wlanauto] <table id=\"wlanavail\" class=\"colorrows inputtable\"> <tr id=\"firstrow\"> <th width=\"30px\"></th> <th width=\"240px\">[!Name] (SSID)</th> <th width=\"110px\">[!Encryption]</th> <th width=\"150px\">[!SignalStrength]</th> <th width=\"200px\">[!MAC]</th> </tr> <tr id=\"loadingrow\"> <td colspan=5 class=\"centertext\"><img src=\"resources/loading.gif\" id=\"loadingWlanScan\"></td> </tr> <tr> <td></td> <td colspan=4><input type=\"button\" id=\"rescan\" value=\"[!Refresh]\" style=\"width: 200px\"></td> </tr> </table> <p></p> [@endif:wlanauto] <table id=\"wlansettings\" class=\"inputTable\"> <tr id=\"wlannamerow\" [@if:wlanauto]style=\"display: none;\"[@endif:wlanauto]> <td>[!WLANName]</td> <td><input type=\"text\" name=\"wlanname\" id=\"wlanname\" [@if:wlanauto]value=\"[@wlanname]\"[@endif:wlanauto] style=\"width: 309px;\"></td> </tr> <tr> <td>[!Password]:</td> <td><input type=\"text\" name=\"wlanpass\" id=\"wlanpass\" style=\"width: 309px;\"></td> </tr> <tr> <td colspan=\"2\" > <input type=\"button\" [@if:wlanauto]id=\"manualcfg\" name=\"manualcfg\" value=\"[!ManualConfig]\"[@endif:wlanauto] [@ifnot:wlanauto]id=\"autocfg\" name=\"autocfg\" value=\"[!AutomaticConfig]\"[@endif:wlanauto] onclick=\"handleMultiform(event, this);\" style=\"width: 180px;\"> </td> </tr> <tr> <td> <input type=\"hidden\" name=\"encinput\" id=\"encinput\" value=\"\"></td> <td id=\"wlaninfo\"></td> </tr> </table> [@ipsettings] [@endif:wlanena] [@ifnot:wlanena] [!NoWLANDevicePluggedIn] <p> <input type=\"button\" name=\"back\" onclick=\"handleMultiform(event, this);\" value=\"[!Back]\" /> </p> [@endif:wlanena] "; // 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/