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"(?s)(?<first><<<<<<< HEAD\n.*?)(?<========)|(?<second>(?=>>>>>>>).*?\n)").unwrap(); let string = "<<<<<<< HEAD import { readdir } from \"fs\"; import { createServer } from \"../src/server.js\"; import Jasmine from 'jasmine'; import dotenv from 'dotenv'; const jasmine = new Jasmine(); ======= import { start } from \"../src/index.js\"; import dotenv from 'dotenv'; import { readdir } from \"fs\"; import Jasmine from 'jasmine'; import { resolve } from 'path'; >>>>>>> c80322f... Refactor codebase. Removed ml parts into separate project. // jasmine.loadConfigFile(`tests/jasmine.json`); const importTests = () => { return new Promise((resolve, reject) => { readdir(`./tests`, (err, files) => { if (err) { reject(err); } files = files.filter(file => { return file.includes(`test.js`); }); console.log(files); files = files.map(file => { const relativePath = `./${file}`; return import(relativePath) .catch(error => { console.error(`** Error loading ` + relativePath + `: `); console.error(error); process.exit(1); }); }); resolve(Promise.all(files)); }); }); }; const runTests = () => { <<<<<<< HEAD dotenv.config(); importTests().then(() => { const server = createServer({ useAuth: false, }); server.options.port = 4040; process.env.GRAPHQL_ENDPOINT = `http://127.0.0.1:4040`; server.start(() => { console.log(`Test server is running on 127.0.0.1:${server.options.port}`); jasmine.execute(); }); ======= const jasmine = new Jasmine(); const environment = process.env.NODE_ENV || `staging`; dotenv.config({ path: resolve(`../src/config/${environment}/.env`), }); importTests().then(async () => { process.env.MONGODB_URIS = `mongodb+srv://f4a-shared-t95ry.gcp.mongodb.net/test`; process.env.GRAPHQL_ENDPOINT = `http://127.0.0.1:4040`; process.env.PORT = `4040`; await start(); console.log(`Test server is running on 127.0.0.1:${server.port}`); jasmine.execute(); >>>>>>> c80322f... Refactor codebase. Removed ml parts into separate project. }); }; runTests();"; // 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/