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

/
/
g

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+\[v=\"(standard)-(\w+)\",g=\"(\w+)\",p=\"(\S+)\"\]\S+\/(returns|mpt_statistics)\/\w+\/(\w+)\/(\w+)"#).unwrap(); let string = "root/4-825-ReturnAndStatsCompositeAPI[v=\"standard-return\",g=\"asofdate\",p=\"{\"asOfDate\":\"2017-07-31\"}\"]/data/share_classes/array[3]/returns/maximum_offering_price/cumulative/one_day root/4-825-ReturnAndStatsCompositeAPI[v=\"standard-return\",g=\"asofdate\",p=\"{\"asOfDate\":\"2017-07-31\"}\"]/data/share_classes/array[3]/mpt_statistics/absolute/gross/one_year/sharpe_ratio root/6-825-ReturnAndStatsCompositeAPI[v=\"standard-benchmark\",g=\"mostRecent\",p=\"{\"asOfDate\":\"\"}\"]/data/share_classes/array[0]/benchmark_types/benchmark_types_breakdown/array[3]/returns/net/cumulative/three_year root/6-825-ReturnAndStatsCompositeAPI[v=\"standard-benchmark\",g=\"mostRecent\",p=\"{\"asOfDate\":\"\"}\"]/data/share_classes/array[1]/benchmark_types/benchmark_types_breakdown/array[3]/mpt_statistics/absolute/net/one_year/skewness root/7-825-ReturnAndStatsCompositeAPI[v=\"standard-index\",g=\"mostRecent\",p=\"{\"asOfDate\":\"\"}\"]/data/share_classes/array[0]/indices/indices_breakdown/array[0]/returns/net/annualized/ten_year root/1-825-ReturnAndStatsCompositeAPI[v=\"standard-category\",g=\"asofdate\",p=\"{\"asOfDate\":\"2017-07-31\"}\"]/data/share_classes/array[1]/peer_categories/morningstar_category/returns/net/cumulative/fifty_two_week root/12-825-ReturnAndStatsCompositeAPI[v=\"timeSeries-return\",g=\"timeSeries\",p=\"{\"rollingPeriod\":\"1Y\",\"numberOfPeriods\":\"5\",\"asOfDate\":\"2016-12-31\",\"startDate\":\"2011-12-31\",\"frequency\":\"1Y\"}\"]/data/share_classes/array[1]/returns_series/returns/array[1]/net/cumulative "; // 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/