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

/
/
gm

Test String

Code Generator

Language

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"(?m)^(((ht|f)(tp)(s)?(:\/\/))?(([0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3})|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))(:\d{1,5})?((\/)([\w\.~%-]+))*(\/)?((\?)(([\w]+)(=[\w\.~%-]+)?((&)([\w]+)(=[\w\.~%-]+)?)*)?)?((#)((([\w]+(=[\w\,\*\.~%-]+)?)(&[\w]+(=[\w\,\*\.~%-]+)?)*)|(:~:text=([\w\.~%-]+\,)?([\w\.~%-]+)(\,[\w\.~%-]+){0,2}))?)?)$").unwrap(); let string = "//Base case 17hieng.com 17hieng.com.my www.17hieng.com.my www.edu.17hieng.com.my 192.168.1.1 //With protocol http://17hieng.com https://192.168.1.1 //With Port http://17hieng.com:8080 https://192.168.1.1:443 //With Path www.edu.17hieng.com.my/edu 192.168.1.1/edu/ http://17hieng.com/edu/edu https://192.168.1.1/ //With query www.edu.17hieng.com.my?query=a&b=c 192.168.1.1/edu/?query=a&b=c@a.com http://17hieng.com/edu/edu?query=a https://192.168.1.1/?query=a&b&c=1 //With Fragment www.edu.17hieng.com.my#about 192.168.1.1/edu?#line=10,20 192.168.1.1/edu/?query=a#t=40,8.0&xywh=160,120,320,240 http://17hieng.com/edu/edu?query=a#:~:text=prefix-,textStart,textEnd,-suffix https://192.168.1.1/?query=a&b&c=1# //domain only 17hieng.com edu.17hieng.com 17hieng.com/ edu.17hieng.com/ //domain + https protocol https://17hieng.com https://edu.17hieng.com https://17hieng.com/ https://edu.17hieng.com/ //domain + http protocol http://17hieng.com http://edu.17hieng.com http://17hieng.com/ http://edu.17hieng.com/ //domain + file path 17hieng.com/cpp edu.17hieng.com/cpp 17hieng.com/cpp/ edu.17hieng.com/cpp/ //domain + https protocol + file path https://17hieng.com/cpp https://edu.17hieng.com/cpp https://17hieng.com/cpp/ https://edu.17hieng.com/cpp/ //domain + http protocol + file path http://17hieng.com/cpp http://edu.17hieng.com/cpp http://17hieng.com/cpp/ http://edu.17hieng.com/cpp/ //domain + multiple folder file path 17hieng.com/cpp/intro edu.17hieng.com/cpp/intro 17hieng.com/cpp/intro/ edu.17hieng.com/cpp/intro/ //domain + https protocol + multiple folder file path https://17hieng.com/cpp/intro https://edu.17hieng.com/cpp/intro https://17hieng.com/cpp/intro/ https://edu.17hieng.com/cpp/intro/ //domain + http protocol + multiple folder file path http://17hieng.com/cpp/intro http://edu.17hieng.com/cpp/intro http://17hieng.com/cpp/intro/ http://edu.17hieng.com/cpp/intro/ //domain + ? 17hieng.com? edu.17hieng.com? 17hieng.com/? edu.17hieng.com/? //domain + https protocol + ? https://17hieng.com? https://edu.17hieng.com? https://17hieng.com/? https://edu.17hieng.com/? //domain + http protocol + ? http://17hieng.com? http://edu.17hieng.com? http://17hieng.com/? http://edu.17hieng.com/? //domain + file path + ? 17hieng.com/cpp? edu.17hieng.com/cpp? 17hieng.com/cpp/? edu.17hieng.com/cpp/? //domain + https protocol + file path + ? https://17hieng.com/cpp? https://edu.17hieng.com/cpp? https://17hieng.com/cpp/? https://edu.17hieng.com/cpp/? //domain + http protocol + file path + ? http://17hieng.com/cpp? http://edu.17hieng.com/cpp? http://17hieng.com/cpp/? http://edu.17hieng.com/cpp/? //domain + multiple folder file path + ? 17hieng.com/cpp/intro? edu.17hieng.com/cpp/intro? 17hieng.com/cpp/intro/? edu.17hieng.com/cpp/intro/? //domain + https protocol + multiple folder file path + ? https://17hieng.com/cpp/intro? https://edu.17hieng.com/cpp/intro? https://17hieng.com/cpp/intro/? https://edu.17hieng.com/cpp/intro/? //domain + http protocol + multiple folder file path + ? http://17hieng.com/cpp/intro? http://edu.17hieng.com/cpp/intro? http://17hieng.com/cpp/intro/? http://edu.17hieng.com/cpp/intro/? //domain + parameter 17hieng.com?name edu.17hieng.com?name 17hieng.com/?name edu.17hieng.com/?name //domain + https protocol + parameter https://17hieng.com?name https://edu.17hieng.com?name https://17hieng.com/?name https://edu.17hieng.com/?name //domain + http protocol + parameter http://17hieng.com?name http://edu.17hieng.com?name http://17hieng.com/?name http://edu.17hieng.com/?name //domain + file path + parameter 17hieng.com/cpp?name edu.17hieng.com/cpp?name 17hieng.com/cpp/?name edu.17hieng.com/cpp/?name //domain + https protocol + file path + parameter https://17hieng.com/cpp?name https://edu.17hieng.com/cpp?name https://17hieng.com/cpp/?name https://edu.17hieng.com/cpp/?name //domain + http protocol + file path + parameter http://17hieng.com/cpp?name http://edu.17hieng.com/cpp?name http://17hieng.com/cpp/?name http://edu.17hieng.com/cpp/?name //domain + multiple folder file path + parameter 17hieng.com/cpp/intro?name edu.17hieng.com/cpp/intro?name 17hieng.com/cpp/intro/?name edu.17hieng.com/cpp/intro/?name //domain + https protocol + multiple folder file path + parameter https://17hieng.com/cpp/intro?name https://edu.17hieng.com/cpp/intro?name https://17hieng.com/cpp/intro/?name https://edu.17hieng.com/cpp/intro/?name //domain + http protocol + multiple folder file path + parameter http://17hieng.com/cpp/intro?name http://edu.17hieng.com/cpp/intro?name http://17hieng.com/cpp/intro/?name http://edu.17hieng.com/cpp/intro/?name //domain + parameter 17hieng.com?name=CheeHieng edu.17hieng.com?name=Chee%20Hieng 17hieng.com/?name=Chee%20Hieng edu.17hieng.com/?name=Chee%20Hieng //domain + https protocol + parameter https://17hieng.com?name=Chee%20Hieng https://edu.17hieng.com?name=Chee%20Hieng https://17hieng.com/?name=Chee%20Hieng https://edu.17hieng.com/?name=Chee%20Hieng //domain + http protocol + parameter http://17hieng.com?name=Chee%20Hieng http://edu.17hieng.com?name=Chee%20Hieng http://17hieng.com/?name=Chee%20Hieng http://edu.17hieng.com/?name=Chee%20Hieng //domain + file path + parameter 17hieng.com/cpp?name=Chee%20Hieng edu.17hieng.com/cpp?name=Chee%20Hieng 17hieng.com/cpp/?name=Chee%20Hieng edu.17hieng.com/cpp/?name=Chee%20Hieng //domain + https protocol + file path + parameter https://17hieng.com/cpp?name=Chee%20Hieng https://edu.17hieng.com/cpp?name=Chee%20Hieng https://17hieng.com/cpp/?name=Chee%20Hieng https://edu.17hieng.com/cpp/?name=Chee%20Hieng //domain + http protocol + file path + parameter http://17hieng.com/cpp?name=Chee%20Hieng http://edu.17hieng.com/cpp?name=Chee%20Hieng http://17hieng.com/cpp/?name=Chee%20Hieng http://edu.17hieng.com/cpp/?name=Chee%20Hieng //domain + multiple folder file path + parameter 17hieng.com/cpp/intro?name=Chee%20Hieng edu.17hieng.com/cpp/intro?name=Chee%20Hieng 17hieng.com/cpp/intro/?name=Chee%20Hieng edu.17hieng.com/cpp/intro/?name=Chee%20Hieng //domain + https protocol + multiple folder file path + parameter https://17hieng.com/cpp/intro?name=Chee%20Hieng https://edu.17hieng.com/cpp/intro?name=Chee%20Hieng https://17hieng.com/cpp/intro/?name=Chee%20Hieng https://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng //domain + http protocol + multiple folder file path + parameter http://17hieng.com/cpp/intro?name=Chee%20Hieng http://edu.17hieng.com/cpp/intro?name=Chee%20Hieng http://17hieng.com/cpp/intro/?name=Chee%20Hieng http://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng //domain + mixed-parameter 17hieng.com?name=Chee%20Hieng&age&id=2200282 edu.17hieng.com?name=Chee%20Hieng&age&id=2200282 17hieng.com/?name=Chee%20Hieng&age&id=2200282 edu.17hieng.com/?name=Chee%20Hieng&age&id=2200282 //domain + https protocol + multi-parameter https://17hieng.com?name=Chee%20Hieng&age&id=2200282 https://edu.17hieng.com?name=Chee%20Hieng&age&id=2200282 https://17hieng.com/?name=Chee%20Hieng&age&id=2200282 https://edu.17hieng.com/?name=Chee%20Hieng&age&id=2200282 //domain + http protocol + multi-parameter http://17hieng.com?name=Chee%20Hieng&age&id=2200282 http://edu.17hieng.com?name=Chee%20Hieng&age&id=2200282 http://17hieng.com/?name=Chee%20Hieng&age&id=2200282 http://edu.17hieng.com/?name=Chee%20Hieng&age&id=2200282 //domain + file path + multi-parameter 17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282 edu.17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282 17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282 edu.17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282 //domain + https protocol + file path + multi-parameter https://17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282 https://edu.17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282 https://17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282 https://edu.17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282 //domain + http protocol + file path + multi-parameter http://17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282 http://edu.17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282 http://17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282 http://edu.17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282 //domain + multiple folder file path + multi-parameter 17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282 edu.17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282 17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282 edu.17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282 //domain + https protocol + multiple folder file path + multi-parameter https://17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282 https://edu.17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282 https://17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282 https://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282 //domain + http protocol + multiple folder file path + parameter http://17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282 http://edu.17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282 http://17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282 http://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200%20282_ //Invalid htp://17hieng.com 17Hieng.c http:/17hieng.com https//17h.my code.17Hi@ng.com 17hieng.com/?=1 17hineg.com// 17Hieng.com/hello world 17Hieng.com< 17hieng.com/h=1 17Hieng.com=2 17hieng.com/?hi=&version 17hieng.com/?hi=1&version&& 17hieng.com/?hi=1&version&q%20 "; // 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/