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

/
/

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"\s{1,2}1. 直接回复此邮件以回复.+\s{1,2}2. 或在线回复").unwrap(); let string = "\\nHi Take ! \\n\\nThank you for welcome me for the stay. \\nI regretted to informed you i can only make a reservation around 7hours later as my husband is currently working .\\nSo, if i book this what is the earliest time i can check in ?\\nHow do i contact when i reach Japan ? \\n\\n\\n1. このメールから直接Everleneさんに返信する\\n2. またはオンラインでEverleneさんに返信する:\\nhttps://www.airbnb.jp/z/q/178989336?eluid=0&euid=fbdfea3f-6ac3-edae-ab50-3b3eae5e9f50\\n\\n------------------------------------------------------------------------\\nリスティング「西新宿駅1分！」を見る：\\nhttps://www.airbnb.jp/rooms/9602551?eluid=1&euid=fbdfea3f-6ac3-edae-ab50-3b3eae5e9f50\\n\\nAirbnbのホストへのメッセージを確認・送る方法：\\nhttps://www.airbnb.jp/help/question/145?eluid=2&euid=fbdfea3f-6ac3-edae-ab50-3b3eae5e9f50\\n\\nAirbnbのヘルプセンターの役立つ情報をご覧ください：\\nhttps://www.airbnb.jp/help?eluid=3&euid=fbdfea3f-6ac3-edae-ab50-3b3eae5e9f50\\n------------------------------------------------------------------------\\n\\nメール配信設定\\nhttps://www.airbnb.jp/users/notifications?eluid=4&euid=fbdfea3f-6ac3-edae-ab50-3b3eae5e9f50\\n\\n### Airbnb ###\\n"; // 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/