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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"gamers_online.*?\s*?([\d,]+)").unwrap(); let string = "[...] <div id=\"about_header_area\" class=\" global\"> <div class=\"about_area_inner_wrapper\"> <div id=\"about_monitor_video\"> <video width=\"100%\" height=\"auto\" autoplay muted loop playsinline poster=\"https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.png\"> <source src=\"https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.webm\" type=\"video/webm\"> <source src=\"https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.mp4\" type=\"video/mp4\"> </video> <div id=\"about_monitor_video_gradient\"></div> </div> <div id=\"about_header\"> <div id=\"about_greeting\"> <div class=\"about_greeting_header\"> <div class=\"steam_logo\"><img src=\"https://cdn.fastly.steamstatic.com/store//about/logo_steam.svg\" alt=\"The logo for Steam\"></div> <div class=\"about_subtitle\">Steam is the ultimate destination for playing, discussing, and creating games.</div> <div class=\"online_stats\"> <div class=\"online_stat\"> <div class=\"online_stat_label gamers_online\">online</div> 36,426,658 </div> <div class=\"online_stat\"> <div class=\"online_stat_label gamers_in_game\">playing now</div> 10,289,777 </div> </div> </div> <div class=\"about_install_wrapper\"> <div class=\"about_install win \"> <a href=\"https://cdn.fastly.steamstatic.com/client/installer/SteamSetup.exe\" class=\"about_install_steam_link\">Install Steam</a> </div> <div class=\"installer_list\"> <div class=\"available_platforms\"> Also available on: </div> <a class=\"platform_icon\" href=\"https://cdn.fastly.steamstatic.com/client/installer/steam.dmg\"> <img src=\"https://cdn.fastly.steamstatic.com/store/about/icon-macos.svg\"> </a> <a class=\"platform_icon\" href=\"https://cdn.fastly.steamstatic.com/client/installer/steam.deb\"> <img src=\"https://cdn.fastly.steamstatic.com/store/about/icon-steamos.svg\"> </a> <a class=\"platform_icon\" href=\"https://support.google.com/chromebook?p=steam_on_chromebook\"> <img src=\"https://cdn.fastly.steamstatic.com/store/about/icon-chromeos.svg\"> </a> </div> </div> </div> </div> </div> <div class=\"learn_more_btn\"> <a href=\"#about_games_cta_area\" class=\"smooth_scroll\"> Learn more <span class=\"down_arrow\"></span> </a> </div> </div> "; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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/