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)("FILENAME" "([^\/:*?"<>|]+)")"#).unwrap(); let string = "130 (UID 1245 BODYSTRUCTURE (((\"TEXT\" \"PLAIN\" (\"CHARSET\" \"UTF-8\") NIL NIL \"QUOTED-PRINTABLE\" 847 17 NIL NIL NIL)(\"TEXT\" \"HTML\" (\"CHARSET\" \"UTF-8\") NIL NIL \"QUOTED-PRINTABLE\" 2009 41 NIL NIL NIL) \"ALTERNATIVE\" (\"BOUNDARY\" \"000000000000929e4505d59042b1\") NIL NIL)(\"IMAGE\" \"JPEG\" (\"NAME\" \"BS_01.jpg\") \"<f_kyetquhw1>\" NIL \"BASE64\" 280364 NIL (\"ATTACHMENT\" (\"FILENAME\" \"BS_(01)_a.jpg\")) NIL)(\"IMAGE\" \"PNG\" (\"NAME\" \"payroll_check_top_format.png\") \"<f_kyetquio3>\" NIL \"BASE64\" 498210 NIL (\"ATTACHMENT\" (\"FILENAME\" \"payroll check top format.png\")) NIL)(\"IMAGE\" \"JPEG\" (\"NAME\" \"missouri_dl_3e_1300x884.jpg\") \"<f_kyetquia2>\" NIL \"BASE64\" 1014040 NIL (\"ATTACHMENT\" (\"FILENAME\" \"missouri_dl_3e_1300x884.jpg\")) NIL)(\"IMAGE\" \"JPEG\" (\"NAME\" \"1040-1-1_N.jpg\") \"<f_kyetquhj0>\" NIL \"BASE64\" 4272596 NIL (\"ATTACHMENT\" (\"FILENAME\" \"1040-1-1_N.jpg\")) NIL) \"MIXED\" (\"BOUNDARY\" \"000000000000929e4705d59042b3\") NIL NIL))"; // 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/