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

/
/
g

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#"class=\"(.*?)\""#).unwrap(); let string = " Xem thêm</a></div></div></div></div><div class=\"em en eo ep eq\"><a href=\"/groups/720798081668729bacr=1591362312%3A1008883346193533%3A1008883346193533%2C0%2C0%3A7%3AKw%3D%3D&amp;multi_permalinks&amp;refid=18\"><span>Xem thêm bài viết</span></a></div></div><a name=\"groupMenuBottom\"></a><div class=\"er\"><h3 class=\"es\">Menu nhóm</h3><ul class=\"bz et\"><li class=\"du\"><table class=\"m bl\"><tbody><tr><td class=\"t\"><a href=\"/groups/720798081668729?view=about&amp;refid=18\">Giới thiệu</a></td><td class=\"n\"></td></tr></tbody></table></li><li class=\"du\"><table class=\"m bl\"><tbody><tr><td class=\"t\"><a href=\"/groups/720798081668729?view=info&amp;refid=18\">Thông tin</a></td><td class=\"n\"></td></tr></tbody></table></li><li class=\"du\"><table class=\"m bl\"><tbody><tr><td class=\"t\"><a href=\"/groups/720798081668729?view=members&amp;refid=18\" id=\"u_0_3\">Thành viên</a></td><td class=\"n\"><span class=\"eu cu\" id=\"u_0_2\">239</span></td></tr></tbody></table></li><li class=\"du\"><table class=\"m bl\"><tbody><tr><td class=\"t\"><a href=\"/groups/720798081668729?view=photos&amp;refid=18\" id=\"u_0_7\">Ảnh</a></td><td class=\"n\"><span class=\"eu cu\" id=\"u_0_6\">1928</span></td></tr></tbody></table></li><li class=\"du\"><table class=\"m bl\"><tbody><tr><td class=\"t\"><a href=\"/groups/720798081668729?view=events&amp;refid=18\">Sự kiện</a></td><td class=\"n\"></td></tr></tbody></table></li><li class=\"du\"><table class=\"m bl\"><tbody><tr><td class=\"t\"><a href=\"/groups/720798081668729?view=files&amp;refid=18\">File</a></td><td class=\"n\"></td></tr></tbody></table></li></ul></div><div class=\"ev\" style=\"display:none\"><div class=\"ew\"><div class=\"ex\"><img src=\"https://static.xx.fbcdn.net/rsrc.php/v3/yR/r/CjVACNCmi_H.png\" width=\"54\" height=\"24\" class=\"ey ez s\" /><div class=\"fa\"><div class=\"fb\"><a href=\"#\" class=\"bt fc bv\">Xem dòng thời gian</a><a href=\"#\" class=\"bt fc bv\">Thêm vào nhóm</a><a href=\"#\" class=\"bt fc bv\">Mời tham gia sự kiện</a></div></div></div></div></div></div><div style=\"display:none\"></div></div></div><div class=\"bz\"><div class=\"fd\"><div class=\"fe\"><table class=\"m\"><tbody><tr><td class=\"t ff\" style=\"width:50%\"><b class=\"fg\">Tiếng Việt</b><a class=\"fh\" href=\"/a/language.php? "; // 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/