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

/
/
gis

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"(?is)<(?:textarea|select).*?>.*?(\{\{\{variable:(.*?)\}\}\}).*?<\/(?:textarea|select)>|<(?:input).+?(value=.*?)(\{\{\{variable:(.+?)\}\}\})?.*?>|(\{\{\{variable:(.*?)\}\}\})").unwrap(); let string = " <section id=\"services\"> <div class=\"container\"> <div class=\"row\"> <div class=\"col-md-12\"> <p>You are using system version: {{{variable:system_version}}}</p> <p>Your address: {{{variable:contact-email-address}}}</p> <form action=\"http://k.loc/content/view/welcome\" class=\"default-form\" enctype=\"multipart/form-data\" method=\"post\" accept-charset=\"utf-8\"> <input type=\"hidden\" name=\"csrfkcmstoken\" value=\"94ee71ada809b9a79d1b723c81020c78\" /> <div class=\"row\"> <div class=\"col-sm-12 form-error\"></div> </div> <div class=\"row\"><div class=\"col-sm-12\"><fieldset id=\"personalinfo\"><legend>Personal information</legend><div class=\"row\"><div class=\"col-sm-12\"> <div class=\"control-label\"> <label for=\"testinput\">Name<span class=\"form-validation-required\"> * </span></label> </div> <div class=\"hint-text\">Enter at least 2 characters and a maximum of 12 characters.</div><input id=\"testinput\" name=\"testinput\" placeholder=\"Enter your name here.\" class=\"input-group width-50\" type=\"text\" value=\"{{{variable:system_name}}} {{{variable:system_login}}}\"><div class=\"row\"><div class=\"col-sm-12\"><div class=\"form-error\"></div></div></div></div></div><div class=\"row\"><div class=\"col-sm-12\"> <div class=\"control-label\"> <label for=\"testpassword\">Password</label> </div> <div class=\"hint-text\">Your password must be at least 12 characters long, contain 1 special character, 1 nunber, 1 lower case character and 1 upper case character.</div><input id=\"testpassword\" name=\"testpassword\" placeholder=\"Enter your password here.\" class=\"input-group width-50\" type=\"password\"><div class=\"row\"><div class=\"col-sm-12\"><div class=\"form-error\"></div></div></div></div></div></fieldset></div></div><div class=\"row\"><div class=\"col-sm-12\"><fieldset id=\"bioinfo\"><legend>Biographical information</legend><div class=\"row\"><div class=\"col-sm-12\"> <div class=\"control-label\"> <label for=\"testtextarea\">Biography</label> <span class=\"hint-text\">A minimum of 40 characters and a maximum of 255 is allowed. This hint is displayed inline.</span> </div> <textarea id=\"testtextarea\" name=\"testtextarea\" placeholder=\"Please enter your biography here.\" class=\"input-group-wide width-100\" rows=\"5\" cols=\"80\">{{{variable:system_name}}} {{{variable:system_login}}}</textarea><div class=\"row\"><div class=\"col-sm-12\"><div class=\"form-error\"></div></div></div></div></div><div class=\"row\"><div class=\"col-sm-12\"> <div class=\"control-label\"> <label for=\"testsummernote\">Interests</label> <span class=\"hint-text\">A minimum of 40 characters is required. This hint is displayed inline.</span> </div> <textarea id=\"testsummernote\" name=\"testsummernote\" class=\"wysiwyg-editor\" placeholder=\"Please enter your interests here.\"><p>{{{variable:system_name}}}<br></p><p>{{{variable:system_login}}}</p><p>{{{variable:activate_url}}}<br></p></textarea></div></div></fieldset></div></div><div class=\"row\"><div class=\"col-sm-12\"><button name=\"testsubmit\" id=\"testsubmit\" type=\"submit\" class=\"btn primary\">Submit<i class=\"zmdi zmdi-arrow-forward\"></i></button></div></div> </form> </div> "; // 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/