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

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)(?:(?:www\.facebook\.com\/(?:(?:(?:video\.php)|(?:watch\/))\?v=\d+|(?:[0-9a-zA-Z-_.]+\/(?:(?:video|(post))(?:s))\/)(?:\d+|(?:\w+\.\d+\/)\d+)))|(?:fb\.watch\/(?:\w|-)+)\/?)").unwrap(); let string = "https://fb.watch/2xoYhkRbF255 https://fb.watch/2xoYhkRbF2/ https://fb.watch/2xo-_v7K6Vj/ https://www.facebook.com/myntpc/videos/842675369629973 https://www.facebook.com/michelle.huang.108889/posts/10157993447446172 https://www.facebook.com/nikololok/videos/t.100000216422619/10153335471682286/?type=2 https://www.facebook.com/something/videos/vb.100001360760001/1371428966245002/?type=2&video_source=user_video_tab https://www.facebook.com/video.php?v=250367532879495 https://www.facebook.com/watch/?v=250367532879495 <iframe src=\"https://www.facebook.com/plugins/post.php?href=https://fb.watch/2xoYhkRbF2/&width=500&show_text=true&appId=290536511140551&height=526\"width=\"500\"height=\"526\"style=\"border:none;overflow:hidden\"scrolling=\"no\"frameborder=\"0\"allowfullscreen=\"true\"allow=\"autoplay;clipboard-write;encrypted-media;picture-in-picture;web-share\"></iframe> <iframesrc=\"https://www.facebook.com/plugins/post.php?href=https://www.facebook.com/michelle.huang.108889/posts/10157993447446172&width=500&show_text=true&appId=290536511140551&height=204\"width=\"500\"height=\"204\"style=\"border:none;overflow:hidden\"scrolling=\"no\"frameborder=\"0\"allowfullscreen=\"true\"allow=\"autoplay;clipboard-write;encrypted-media;picture-in-picture;web-share\"></iframe> <div class=\"fb-post\" data-href=\"https://www.facebook.com/DailyMailVideo/posts/3729983233749236\" data-width=\"500\" data-show-text=\"true\"><blockquote cite=\"https://www.facebook.com/DailyMailVideo/posts/3729983233749236\" class=\"fb-xfbml-parse-ignore\"><p>A new set of eleph-antlers!</p>由 <a href=\"https://www.facebook.com/DailyMailVideo/\">Daily Mail Video</a> 發佈於&nbsp;<a href=\"https://www.facebook.com/DailyMailVideo/posts/3729983233749236\">2021年1月5日 星期二</a></blockquote></div> <iframesrc=\"https://www.facebook.com/plugins/video.php?height=316&href=https://www.facebook.com/1243823171/videos/10217863771006297/&show_text=false&width=560\"width=\"560\"height=\"316\"style=\"border:none;overflow:hidden\"scrolling=\"no\"frameborder=\"0\"allowfullscreen=\"true\"allow=\"autoplay;clipboard-write;encrypted-media;picture-in-picture;web-share\"allowFullScreen=\"true\"></iframe> "; // 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/