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
Processing...

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)(?P<syslog_date>\S+\s+\d+\s+\d+:\d+:\d+)\s+0\s+(?P<log_date>\d+-\d+-\d+T\d+:\s\d+:\d+[^\s]+)\s+.*?(?:(?P<device>[^\s:]+)\s+)?(?P<application>ora_[^\s:]+_Audit)\s+-\s+-\s+Audit\[\d+\]:\s+(?:[^]]+]\s+)?(?:LENGTH:\s+\"(?P<length>\d+)\".*?)?SESSIONID:(?:\[\d+\])?\s+\"(?P<sessionid>\d+)\".*?ENTRYID:(?:\[\d+\])?\s+\"(?P<entryid>\d+)\".*?(?:STATEMENT:(?:\[\d+\])?\s+\"(?P<statement>.*?)\")?.*?USERID:(?:\[\d+\])?\s+\"(?P<userid>.*?)\".*?(?:USERHOST:(?:\[\d+\])\s+"(?:(?P<host_domain>[^\\"]+)\\+)?(?P<userhost>[^"]*)")?\s+(?:TERMINAL:(?:\[\d+\])\s+"(?P<terminal>[^"]*)"\s+)?ACTION:(?:\[\d+\])?\s+\"(?P<action>\d+)\".*?RETURNCODE:(?:\[\d+\])?\s+\"(?P<code>.*?)\".*?(?:COMMENT\$TEXT:(?:\[\d+\])?.*?\"Authenticated\s+by:\s+(?P<auth_by>\S+)(?:\;\s+Client\s+address:\s+\(ADDRESS\=\(PROTOCOL\=tcp\)\(HOST\=(?P<host>\d+\.\d+\.\d+\.\d+)\)\(PORT\=(?P<port>\d+)\)\).*?|"\s+)|OBJ\$CREATOR:(?:\[\d+\])?\s+\"(?P<objcreator>[^"]*)"\s+.*?OBJ\$NAME:(?:\[\d+\])?\s+\"(?P<objname>[^"]*)"\s+)OS\$USERID:(?:\[\d+\])?\s+\"(?P<osuserid>[^"]*)"\s*(?:(?!PRIV\$)\S+\s+)*(?:PRIV\$USED:(?:\[\d+\])?\s+"(?P<priv>[^"]*)")?"#).unwrap(); let string = "Mar 31 00:02:54 0 2020-03-31T00: 02:53.629415+02:00 localhost ora_AM_Audit - - Audit[29579]: LENGTH: \"379\" SESSIONID:[9] \"130549450\" ENTRYID:[1] \"1\" STATEMENT:[1] \"1\" USERID:[15] \"EFACTURA_CDATOS\" USERHOST:[9] \"EFPRE-TRX\" ACTION:[3] \"100\" RETURNCODE:[1] \"0\" COMMENT$TEXT:[102] \"Authenticated by: DATABASE; Client address: (ADDRESS=(PROTOCOL=tcp)(HOST=192.168.200.237)(PORT=44530))\" OS$USERID:[9] \"efamerica\" DBID:[10] \"3787855415\" PRIV$USED:[1] \"5\" CURRENT_USER:[15] \"EFACTURA_CDATOS\""; // 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/