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

/
/
gms

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#"(?ms),\s*("subresource_uris":.[^}]*[}])"#).unwrap(); let string = "{ \"first_page_uri\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?PageSize=1000&Page=0\", \"end\": 387, \"previous_page_uri\": null, \"uri\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?PageSize=1000&Page=0\", \"page_size\": 1000, \"start\": 0, \"usage_records\": [ { \"category\": \"wireless-usage\", \"description\": \"SIM Usage\", \"account_sid\": \"ACd7a7c24a3c7b0b0ddcde452fd6c18aae\", \"start_date\": \"2023-01-01\", \"end_date\": \"2023-01-31\", \"as_of\": \"2023-02-05T06:53:40+00:00\", \"count\": \"0\", \"count_unit\": \"units\", \"usage\": \"0\", \"usage_unit\": \"units\", \"price\": \"0\", \"price_unit\": \"usd\", \"api_version\": \"2010-04-01\", \"uri\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=wireless-usage&StartDate=2023-01-01&EndDate=2023-01-31\", \"subresource_uris\": { \"all_time\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/AllTime.json?Category=wireless-usage\", \"today\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Today.json?Category=wireless-usage\", \"yesterday\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yesterday.json?Category=wireless-usage\", \"this_month\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/ThisMonth.json?Category=wireless-usage\", \"last_month\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=wireless-usage\", \"daily\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Daily.json?Category=wireless-usage\", \"monthly\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Monthly.json?Category=wireless-usage\", \"yearly\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yearly.json?Category=wireless-usage\" } }, { \"category\": \"pv-basic-rooms\", \"description\": \"Go Rooms\", \"account_sid\": \"ACd7a7c24a3c7b0b0ddcde452fd6c18aae\", \"start_date\": \"2023-01-01\", \"end_date\": \"2023-01-31\", \"as_of\": \"2023-02-05T06:53:40+00:00\", \"count\": \"0\", \"count_unit\": \"\", \"usage\": \"0\", \"usage_unit\": \"\", \"price\": \"0\", \"price_unit\": \"usd\", \"api_version\": \"2010-04-01\", \"uri\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=pv-basic-rooms&StartDate=2023-01-01&EndDate=2023-01-31\", \"subresource_uris\": { \"all_time\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/AllTime.json?Category=pv-basic-rooms\", \"today\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Today.json?Category=pv-basic-rooms\", \"yesterday\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yesterday.json?Category=pv-basic-rooms\", \"this_month\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/ThisMonth.json?Category=pv-basic-rooms\", \"last_month\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=pv-basic-rooms\", \"daily\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Daily.json?Category=pv-basic-rooms\", \"monthly\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Monthly.json?Category=pv-basic-rooms\", \"yearly\": \"/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yearly.json?Category=pv-basic-rooms\" } }, "; // 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/