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

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)Zweckfreibaum").unwrap(); let string = "//************* Russel ************** //++++++++++++ App.jsx ++++++++++++++ import React from \"react\"; import { DragonList } from \"./DragonList\"; import dragons from './dragons'; export default function App() {7 const [minAge, setMinAge] = React.useState(17); const [type, setType] = React.useState('All'); console.log(dragons); return ( <div> <h1>The Dragons:</h1> <DragonList dragons={dragons} minAge={minAge} type={type}/> <span>Minimum Age: {minAge}</span> <button type=\"button\" onClick={ () => setMinAge(age => age - 1) }> Show younger dragons </button> <button type=\"button\" onClick={ () => setMinAge(age => age + 1) }> Show older dragons </button> <button type=\"button\" onClick={ () => setType('All') }> Show all dragons </button> <button type=\"button\" onClick={ () => setType('Fire') }> Show fire dragons </button> </div> ) } //++++++++++++++ Main.jsx ++++++++++++++++++ import { StrictMode } from 'react' import { createRoot } from 'react-dom/client' import './index.css' import GiggnGoggn from './App.jsx' createRoot(document.getElementById('root')).render( <StrictMode> <GiggnGoggn /> </StrictMode>, ) //++++++++++++++ dragon.js++++++++++++++ export default dragons = [ { name: \"Skril\", type: \"Lightning\", age: 16, }, { name: \"Nightmare\", type: \"Fire\", age: 22, }, { name: \"Deadly Nadder\", type: \"Magnesium\", age: 16, }, { name:\"Night Fury\", type: \"Plasma\", age: 18, }, ]; //++++++++++++++++++++++ DragonList.jsx+++++++++++++++++++ import { Dragon } from \"./Dragon\"; export function DragonList({dragons, minAge, type}) { const filteredDragons = dragons.filter( dragon => (dragon.age >= minAge) && (type === 'All' ? true : dragon.type === type) ); console.log('filteredDragons', {filteredDragons}); return ( <div> {filteredDragons.map((dragon, index) => <Dragon key={index} {...dragon} /> )} </div> ); } //++++++++++++++++++ dragon.jsx +++++++++++++++++++++++++ export function Dragon({ name, type, age }) { return ( <div> <h2>{name}</h2> <p>Type: {type}</p> <p>Age: {age} years</p> </div> ); } "; // 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/