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)^\[assembly: AssemblyInformationalVersion\(\"(?P<version>[0-9]+(\.([0-9]+|\*)){1,3})\"\)\].*$"#).unwrap(); let string = "using System.Reflection; using System.Resources; using System.Runtime.InteropServices; // General Information about an assembly is controlled through the following // set of attributes. Change these attribute values to modify the information // associated with an assembly. [assembly: AssemblyTitle(\"MRC+\")] [assembly: AssemblyDescription(\"MRC+ Configuration\")] [assembly: AssemblyConfiguration(\"\")] [assembly: AssemblyCompany(\"Kongsberg Seatex AS\")] [assembly: AssemblyProduct(\"MRC+\")] [assembly: AssemblyCopyright(\"Copyright © Kongsberg Seatex AS 2009 - 2015\")] [assembly: AssemblyTrademark(\"\")] [assembly: AssemblyCulture(\"\")] // Setting ComVisible to false makes the types in this assembly not visible // to COM components. If you need to access a type in this assembly from // COM, set the ComVisible attribute to true on that type. [assembly: ComVisible(false)] // The following GUID is for the ID of the typelib if this project is exposed to COM [assembly: Guid(\"fd48eeca-4024-4955-aae1-e2279d13d262\")] // Version information for an assembly consists of the following four values: // // Major Version // Minor Version // Build Number // Revision // // You can specify all the values or you can default the Build and Revision Numbers // by using the '*' as shown below: // [assembly: AssemblyVersion(\"5.6.*\")] [assembly: AssemblyVersion(\"5.7.*\")] [assembly: AssemblyFileVersion(\"5.7.1\")] [assembly: AssemblyInformationalVersion(\"5.7.1.7\")] //Hurra! [assembly: NeutralResourcesLanguage(\"en\")] "; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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/