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

r"
"
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#"(?<=src=\\").*?(?=\\")"#).unwrap(); let string = "{\"Items\":[{\"ItemID\":10198,\"ItemType\":null,\"Subject\":null,\"SubjectID\":14,\"Area\":null,\"AreaID\":18,\"Topic\":null,\"TopicID\":18,\"SubTopicID\":0,\"ItemBankName\":null,\"Direction\":\"\",\"ItemTitle\":\"Q.53\",\"IsApproved\":false,\"Item\":\"\\u003cp\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003eThe\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e efficiency of the screw\\u0026nbsp;\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003ein %\\u0026nbsp;\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003eupto\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e two decimal places is\\u0026nbsp;\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e[quizky-text]\\u003c/span\\u003e\\u003c/p\\u003e\",\"ItemPassageID\":352,\"Passage\":\"\\u003cp\\u003e\\u003cstrong\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003eStatement\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e for Linked Answer Questions 52 and 53:\\u0026nbsp;\\u003c/span\\u003e\\u003c/strong\\u003e\\u003cbr /\\u003e \\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003eA load of 30 KN is raised by means of a screw jack having square threaded screw of pitch 12 mm. The spindle diameter is 50 mm. If a force of 350 N is applied at the end of a lever to raise the load, co-efficient of friction\\u0026nbsp;\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003eis\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e 0.15.\\u003c/span\\u003e\\u003c/p\\u003e\",\"PassageTitle\":null,\"IsLinkedQuestion\":false,\"Points\":0,\"Explanation\":\"\\u003cp\\u003e\\u003cspan style=\\\"font-family: Symbol;\\\"\\u003eh\\u003c/span\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e =\\u0026nbsp;\\u003c/span\\u003e\\u003cimg style=\\\"vertical-align: bottom;\\\" src=\\\"QUIZKYIMAGEREPO/docximg_1128711867_image197.png\\\" alt=\\\"\\\" width=\\\"54\\\" height=\\\"32\\\" data-docx-image=\\\"image197.emf\\\" /\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e =\\u0026nbsp;\\u003c/span\\u003e\\u003cimg style=\\\"vertical-align: bottom;\\\" src=\\\"QUIZKYIMAGEREPO/docximg_1128711867_image198.png\\\" alt=\\\"\\\" width=\\\"40\\\" height=\\\"31\\\" data-docx-image=\\\"image198.emf\\\" /\\u003e\\u003cspan style=\\\"font-size: 14.7px;\\\"\\u003e = 33%\\u003c/span\\u003e\\u003c/p\\u003e\",\"ItemBankID\":0,\"LOD\":null,\"LODID\":2,\"ItemBank\":0,\"QuestionPaper\":0,\"IsProofRead\":false,\"CorrectIndex\":0,\"QuestionPaperSectionID\":0,\"ItemOptionModel\":null}],\"ItemOptions\":[{\"ItemOptionID\":37637,\"ItemID\":0,\"Option\":\"\\u003cp\\u003e\\u003cspan style=\\\"font-family: Arial; font-size: 12px;\\\"\\u003e\\u0026nbsp;\\u003c/span\\u003e\\u003cspan style=\\\"font-family: Arial; font-size: 12px;\\\"\\u003e33.36\\u003c/span\\u003e\\u003c/p\\u003e\",\"RHSOption\":null,\"MarkedIndex\":null,\"OrderNumber\":null,\"OptionIndex\":0,\"IsCorrect\":false,\"IsHTML\":false,\"RHSIsHTML\":false,\"ColumnID\":0},{\"ItemOptionID\":37638,\"ItemID\":0,\"Option\":\"\\u003cp\\u003e\\u003cspan style=\\\"font-family: Arial; font-size: 12px;\\\"\\u003e\\u0026nbsp;\\u003c/span\\u003e\\u003cspan style=\\\"font-family: Arial; font-size: 12px;\\\"\\u003e33.36\\u003c/span\\u003e\\u003c/p\\u003e\",\"RHSOption\":null,\"MarkedIndex\":null,\"OrderNumber\":null,\"OptionIndex\":0,\"IsCorrect\":false,\"IsHTML\":false,\"RHSIsHTML\":false,\"ColumnID\":0}]}"; // 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/