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

~
~
mUg

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"(?mU)[^<>](?![^<]*>|[^<>]*<\/)(?!\s\#\s)(\#\S[^<>](?![^<]*>|[^<>]*<\/)(.*?)\S\#)").unwrap(); let string = "With # : #Zhong Lun Law Firm# With # : #Algeria’s new Investment Law# With # : #中伦律师事务所# With # : #Victor I-Hsiu Chang# With # : #叶姝欐# With # : #Nguyen Anh Tuan# With # : #AnJie Law Firm# With # : #锦天城律师事务所# <section id=\"Capital\" class=\"vantage-bg-grey\"> <p id=\"Capital\" class=\"DOTY_DOTY-Number\" style=\"background-color: #ec1c24; color: #ffffff; font-weight: bold; font-size: 20px; padding: 5px; text-align: justify;\"><a style=\"color: white;\" href=\"#Capital\"><u>CAPITAL MARKETS</u></a></p><section id=\"Capital\" class=\"vantage-bg-grey\"> <p id=\"Capital\" class=\"DOTY_DOTY-Number\" style=\"background-color: #ec1c24; color: #ffffff; font-weight: bold; font-size: 20px; padding: 5px; text-align: justify;\"><a style=\"color: white;\" href=\"#Capital\"><u>CAPITAL MARKETS</u></a></p><section id=\"Capital\" class=\"vantage-bg-grey\"> <p id=\"Capital\" class=\"DOTY_DOTY-Number\" style=\"background-color: #ec1c24; color: #ffffff; font-weight: bold; font-size: 20px; padding: 5px; text-align: justify;\"><a style=\"color: white;\" href=\"#Capital\"><u>CAPITAL MARKETS</u></a></p><section id=\"Capital\" class=\"vantage-bg-grey\"> <p id=\"Capital\" class=\"DOTY_DOTY-Number\" style=\"background-color: #ec1c24; color: #ffffff; font-weight: bold; font-size: 20px; padding: 5px; text-align: justify;\"><a style=\"color: white;\" href=\"#Capital\"><u>CAPITAL MARKETS</u></a></p> one <p>two</p> three <p class=\"test\">four</p> five <a>six</a> seven <p> eight nine <p/> ten <a style=\"text-decoration: none;\" href=\"https://beta2.law.asia/china/china-top-lawyers-2022/\"><button style=\"width: 100%; font-size: 18px; letter-spacing: 1px; padding: 14px 20px; color: #666; border-color: #F4F4F4; background-color: #fff; background-image: linear-gradient(to bottom,rgba(0,0,0,.01) 0,rgba(0,0,0,.02) 100%); background-repeat: repeat-x; border-radius: 5px; a: hover{background-color:#000;\"><span style=\"color: #c94f3f; font-weight: bold; text-transform: uppercase;\">China</span></button> </a> [vc_column_text]<a style=\"text-decoration: none;\" href=\"https://beta2.law.asia/asia/lawyers/singapore-lawyers/\"><button style=\"width: 100%; font-size: 18px; letter-spacing: 1px; padding: 14px 20px; color: #666; border-color: #F4F4F4; background-color: #fff; background-image: linear-gradient(to bottom,rgba(0,0,0,.01) 0,rgba(0,0,0,.02) 100%); background-repeat: repeat-x; border-radius: 5px; a: hover{background-color:#000;\"><span style=\"color: #c94f3f; font-weight: bold; text-transform: uppercase;\">Singapore</span></button> </a>[/vc_column_text][/vc_column][vc_column width=\"1/2\"][vc_column_text] [vc_column_text]<a style=\"text-decoration: none;\" href=\"https://beta2.law.asia/asia/lawyers/singapore-lawyers/\"><span style=\"color: #c94f3f; font-weight: bold; text-transform: uppercase;\">Singapore</span></a>[/vc_column_text][/vc_column][vc_column width=\"1/2\"][vc_column_text] <a href=\"https://beta2.law.asia/law-firm/drew-napier/\">Drew &amp; Napier</a><br> Drew &amp; Napier<br> <a href=\"https://beta2.law.asia/law-firm/allen-overy/\">Allen &amp; Overy</a><br> Allen &amp; Overy<br> <a href=\"https://beta2.law.asia/asia/\">Robert Hasan</a><br> Robert Hasan<br> 华进律师事务所<br> 华进律师事务所<br> <a href=\"https://beta2.law.asia/law-firm/deep-far-attorneys-at-law/\">Deep &amp; Far</a><br> Deep &amp; Far #<a href=\"https://beta2.law.asia/law-firm/drew-napier/\">Drew &amp; Napier</a>#"; // 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/