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
Processing...

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"<(.)*>").unwrap(); let string = "<p><b>Vancouver</b> (<span class=\"rt-commentedText nowrap\"><span class=\"IPA nopopups noexcerpt\"><a href=\"/wiki/Help:IPA/English\" title=\"Help:IPA/English\">/<span style=\"border-bottom:1px dotted\"><span title=\"'v' in 'vie'\">v</span><span title=\"/æ/: 'a' in 'bad'\">æ</span><span title=\"'n' in 'nigh'\">n</span><span title=\"/ˈ/: primary stress follows\">ˈ</span><span title=\"'k' in 'kind'\">k</span><span title=\"/uː/: 'oo' in 'goose'\">uː</span><span title=\"'v' in 'vie'\">v</span><span title=\"/ər/: 'er' in 'letter'\">ər</span></span>/</a></span> <span class=\"nowrap\" style=\"font-size:85%\">(<span class=\"unicode haudio\"><span class=\"fn\"><span style=\"white-space:nowrap;margin-right:.25em;\"><a href=\"/wiki/File:EN-Vancouver.ogg\" title=\"About this sound\"><img alt=\"About this sound\" src=\"//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Loudspeaker.svg/11px-Loudspeaker.svg.png\" decoding=\"async\" srcset=\"//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Loudspeaker.svg/17px-Loudspeaker.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Loudspeaker.svg/22px-Loudspeaker.svg.png 2x\" data-file-width=\"20\" data-file-height=\"20\" width=\"11\" height=\"11\"></a></span><a href=\"//upload.wikimedia.org/wikipedia/commons/4/44/EN-Vancouver.ogg\" class=\"internal\" title=\"EN-Vancouver.ogg\">listen</a></span></span>)</span></span> <a href=\"/wiki/Help:Pronunciation_respelling_key\" title=\"Help:Pronunciation respelling key\"><i title=\"English pronunciation respelling\">van-<span style=\"font-size:90%\">KOO</span>-vər</i></a>) is a major city in <a href=\"/wiki/Western_Canada\" title=\"Western Canada\">western Canada</a>, located in the <a href=\"/wiki/Lower_Mainland\" title=\"2016 Canadian Census\">Lower Mainland</a> region of <a href=\"/wiki/British_Columbia\" title=\"British Columbia\">British Columbia</a>. As the <a href=\"/wiki/List_of_cities_in_British_Columbia\" title=\"List of cities in British Columbia\">most populous city</a> in the province, the <a href=\"/wiki/2016_Canadian_Census\" class=\"mw-redirect\" title=\"\">2016 census</a> recorded 631,486 people in the city, up from 603,502 in 2011. The <a href=\"/wiki/Greater_Vancouver\" title=\"Greater Vancouver\">Greater Vancouver</a> area had a population of 2,463,431 in 2016, making it the <a href=\"/wiki/List_of_census_metropolitan_areas_and_agglomerations_in_Canada#List\" title=\"\">third-largest metropolitan area in Canada</a>. Vancouver has the highest population density in Canada, with over 5,400 people per square kilometre.<sup id=\"cite_ref-5\" class=\"reference\"><a href=\"#cite_note-5\">[5]</a></sup><sup id=\"cite_ref-6\" class=\"reference\"><a href=\"#cite_note-6\">[6]</a></sup> Vancouver is one of the most <a href=\"/wiki/Ethnic_origins_of_people_in_Canada\" title=\"Ethnic origins of people in Canada\">ethnically</a> and linguistically diverse cities in Canada: 52 percent of its residents are not native English speakers,<sup id=\"cite_ref-pop2006-Van_7-0\" class=\"reference\"><a href=\"#cite_note-pop2006-Van-7\">[7]</a></sup><sup id=\"cite_ref-8\" class=\"reference\"><a href=\"#cite_note-8\">[8]</a></sup> 48.9 percent are native speakers of neither English nor French, and 50.6 percent of residents belong to <a href=\"/wiki/Visible_minority\" title=\"Visible minority\">visible minority</a> groups.<sup id=\"cite_ref-9\" class=\"reference\"><a href=\"#cite_note-9\">[9]</a></sup> </p>"; // 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/