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

/
/
gm

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)(.*?<SYSD:INFO>.*?severity="info".*?(sys=("SecureWeb"|"SecureNet").*?(action="pass"|fwrule="60001")).*|.*?<LOC\d:NOTE>.*)"#).unwrap(); let string = "09 04 2019 10:46:13 10.69.137.81 <SYSD:INFO> 2019:09:04-10:46:13 wf-tg-utm-2 httpproxy[26178]: id=\"0001\" severity=\"info\" sys=\"SecureWeb\" sub=\"http\" name=\"http access\" action=\"pass\" method=\"GET\" srcip=\"192.168.128.67\" dstip=\"104.31.8.169\" user=\"\" group=\"\" ad_domain=\"\" statuscode=\"403\" cached=\"0\" profile=\"REF_HttProContaInterNetwo10 (Wireless Hotspot)\" filteraction=\"REF_HttCffDefauAllowGuest (Default Allow (Guest))\" size=\"3057\" request=\"0xd50f0e00\" url=\"http://exmaple.com/\" referer=\"\" error=\"\" authtime=\"0\" dnstime=\"92\" aptptime=\"88\" cattime=\"92\" avscantime=\"4513\" fullreqtime=\"18114\" device=\"0\" auth=\"0\" ua=\"\" exceptions=\"ssl,certcheck,certdate,application,patience\" category=\"177\" reputation=\"neutral\" categoryname=\"Content Server\" sandbox=\"-\" content-type=\"text/html\" 09 04 2019 10:38:33 10.69.137.81 <LOC6:NOTE> 2019:09:04-10:38:33 wf-tg-utm-2 httpd: 192.168.129.115 - - [04/Sep/2019:10:38:33 +0100] \"GET /bag?v=1 HTTP/1.1\" 302 - 09 05 2019 13:44:24 10.69.137.81 <SYSD:INFO> 2019:09:05-13:44:24 wf-tg-utm-2 httpproxy[26178]: id=\"0001\" severity=\"info\" sys=\"SecureWeb\" sub=\"http\" name=\"http access\" action=\"pass\" method=\"GET\" srcip=\"10.69.202.41\" dstip=\"185.187.118.2\" user=\"Da088518\" group=\"AD Proxy Users (WBS)\" ad_domain=\"CYMRU\" statuscode=\"200\" cached=\"0\" profile=\"REF_HttProContaInterNetwo4 (Clients (DHCP/Static))\" filteraction=\"REF_HttCffDefauAllow (Default Allow)\" size=\"42\" request=\"0xdab72a00\" url=\"http://lgen.idgconnect.com/t/1hxnDKGABJ.png\" referer=\"\" error=\"\" authtime=\"679\" dnstime=\"3236\" aptptime=\"86\" cattime=\"20119\" avscantime=\"975\" fullreqtime=\"276035\" device=\"0\" auth=\"2\" ua=\"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 10.0; WOW64; Trident/7.0; .NET4.0C; .NET4.0E; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; Tablet PC 2.0; wbx 1.0.0; Microsoft Outlook 16.0.4873; Microsoft Outlook 16.0.4873; ms-office; MSOffice \" exceptions=\"\" category=\"105\" reputation=\"neutral\" categoryname=\"Business\" sandbox=\"-\" content-type=\"image/gif\" 09 05 2019 13:44:24 10.69.137.81 <SYSD:INFO> 2019:09:05-13:44:24 wf-tg-utm-2 httpproxy[26178]: id=\"0001\" severity=\"info\" sys=\"SecureWeb\" sub=\"http\" name=\"http access\" action=\"pass\" method=\"CONNECT\" srcip=\"10.69.202.41\" dstip=\"104.24.31.38\" user=\"Da088518\" group=\"AD Proxy Users (WBS)\" ad_domain=\"CYMRU\" statuscode=\"200\" cached=\"0\" profile=\"REF_HttProContaInterNetwo4 (Clients (DHCP/Static))\" filteraction=\"REF_HttCffDefauAllow (Default Allow)\" size=\"134746\" request=\"0xd55f1800\" url=\"https://image.chitra.live/\" referer=\"\" error=\"\" authtime=\"404\" dnstime=\"1204\" aptptime=\"98\" cattime=\"20482\" avscantime=\"0\" fullreqtime=\"2888600\" device=\"0\" auth=\"2\" ua=\"Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 10.0; WOW64; Trident/7.0; .NET4.0C; .NET4.0E; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; Tablet PC 2.0; wbx 1.0.0; Microsoft Outlook 16.0.4873; Microsoft Outlook 16.0.4873)\" exceptions=\"\" category=\"177\" reputation=\"neutral\" categoryname=\"Content Server\" 09 05 2019 13:44:24 10.69.137.81 <SYSD:INFO> 2019:09:05-13:44:23 wf-tg-utm-2 ulogd[10129]: id=\"2001\" severity=\"info\" sys=\"SecureNet\" sub=\"packetfilter\" name=\"Packet dropped\" action=\"drop\" fwrule=\"60001\" initf=\"eth7\" srcmac=\"44:e4:d9:8f:dd:c2\" dstmac=\"00:1a:8c:f0:ca:67\" srcip=\"40.100.174.18\" dstip=\"159.86.176.10\" proto=\"6\" length=\"40\" tos=\"0x00\" prec=\"0x00\" ttl=\"240\" srcport=\"993\" dstport=\"54752\" tcpflags=\"RST\" "; // 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/