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

r"
"
s

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)(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2},\d{3}) \[.*\] ERROR com.encima.project.h2y.handlers.XML.XMLBusinessComparator - \[Tx: (\d{8,12})\] Hotel id (\d*) : No weekends found for given hotel with the query criteria QueryData\(arrivaldate=(\d{4}-\d{2}-\d{2}), nbofnights=(\d), nbofadults=(\d), nbofchildren=(\d), agechildren=.{0,4}, nbofbabies=\d, agebabies=.{0,4}, nbofrooms=(\d), language=(\w{2}), affiliate=(\d{0,5}), hotelIds=.*").unwrap(); let string = "2016-06-22 00:00:15,759 [http-nio-8110-exec-12] ERROR com.encima.project.h2y.handlers.XML.XMLBusinessComparator - [Tx: 710117088] Hotel id 10500 : No weekends found for given hotel with the query criteria QueryData(arrivaldate=2016-09-05, nbofnights=6, nbofadults=2, nbofchildren=0, agechildren=null, nbofbabies=0, agebabies=null, nbofrooms=1, language=es, affiliate=4894, hotelIds=[10628, 12175, 9869, 12905, 11670, 10500, 10822, 12132, 6309, 12559])"; // 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/