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

import re regex = re.compile(r"Zwechfreibaum01", flags=re.MULTILINE) test_str = ("//++++++++++08++++++++++++++++++++\n\n" "/+++++++++++ App.jsx ++++++++++++\n" "import React from \"react\";\n" "import PictureListAs05 from \"./components/PictureListAs05.jsx\";\n" "import PictureListAs06 from \"./components/PictureListAs06.jsx\";\n\n" "export default function App() {\n" " return (\n" " <div>\n" " <h1>AS05 – Bilderliste</h1>\n" " <div style={{ display: \"flex\", gap: \"2rem\" }}>\n" " <PictureListAs05 grenze={80} farbe1=\"green\" farbe2=\"red\" />\n" " <PictureListAs06 grenze={100} farbe1=\"blue\" farbe2=\"orange\" />\n" " </div>\n" " </div>\n" " );\n" "}\n\n\n" "//+++++++++++++ PictureList05.jsx +++++++++++++++++++++++++\n\n" "import React from \"react\";\n" "import ShowPictureList from \"./ShowPictureList.jsx\";\n\n" "const BILDER = [\n" " { url: \"https://picsum.photos/seed/a/400\", alt: \"Wald\", datum: \"2025-02-01\", zahl: 120 },\n" " { url: \"https://picsum.photos/seed/b/400\", alt: \"Gebirge\", datum: \"2025-02-02\", zahl: 60 },\n" " { url: \"https://picsum.photos/seed/c/400\", alt: \"Meer\", datum: \"2025-02-03\", zahl: 200 },\n" " { url: \"https://picsum.photos/seed/d/400\", alt: \"Stadt\", datum: \"2025-02-04\", zahl: 75 },\n" " { url: \"https://picsum.photos/seed/e/400\", alt: \"Wüste\", datum: \"2025-02-05\", zahl: 95 },\n" " { url: \"https://picsum.photos/seed/f/400\", alt: \"Wiese\", datum: \"2025-02-06\", zahl: 50 },\n" "];\n\n" "export default function PictureListAs05({ grenze, farbe1, farbe2 }) {\n" " const GRENZE = grenze;\n" " const FARBE1 = farbe1;\n" " const FARBE2 = farbe2;\n\n" " return (\n" " <div>\n" " <ShowPictureList\n" " bilder={BILDER}\n" " grenze={GRENZE}\n" " farbe1={FARBE1}\n" " farbe2={FARBE2}\n" " />\n" " </div>\n" " );\n" "}\n\n" "//++++++++++++++ PictureList06.jsx+++++++++++++++++++++++\n\n" "import React from \"react\";\n" "import ShowPictureList from \"./ShowPictureList.jsx\";\n\n" "const BILDER = [\n" " { url: \"https://placebear.com/400/400\", alt: \"Bär im Wald\", datum: \"2025-02-01\", zahl: 120 },\n" " { url: \"https://placebear.com/401/400\", alt: \"Bär am Berg\", datum: \"2025-02-02\", zahl: 60 },\n" " { url: \"https://placebear.com/402/400\", alt: \"Bär am See\", datum: \"2025-02-03\", zahl: 200 },\n" " { url: \"https://placebear.com/403/400\", alt: \"Bär in der Stadt\",datum: \"2025-02-04\", zahl: 75 },\n" " { url: \"https://placebear.com/404/400\", alt: \"Bär in der Wüste\",datum: \"2025-02-05\", zahl: 95 },\n" " { url: \"https://placebear.com/405/400\", alt: \"Bär auf der Wiese\",datum: \"2025-02-06\", zahl: 50 },\n" "];\n\n" "export default function PictureListAs06({ grenze, farbe1, farbe2 }) {\n" " const GRENZE = grenze;\n" " const FARBE1 = farbe1;\n" " const FARBE2 = farbe2;\n\n" " return (\n" " <div>\n" " <ShowPictureList\n" " bilder={BILDER}\n" " grenze={GRENZE}\n" " farbe1={FARBE1}\n" " farbe2={FARBE2}\n" " />\n" " </div>\n" " );\n" "}\n\n\n" "//+++++++++++++++++++ PictureList.jsx ++++++++++++++++++++\n\n" "import React, { useState } from \"react\";\n\n" "export default function ShowPictureList({ bilder, grenze, farbe1, farbe2 }) {\n" " const threshold = Number(grenze) || 0;\n\n" " const imageArrayIndex = useState(0);\n" " const currentIndex = imageArrayIndex[0];\n" " const setCurrentIndex = imageArrayIndex[1];\n" " const borderColor = bilder[currentIndex].zahl > threshold ? farbe1 : farbe2;\n" " const currentImage = bilder[currentIndex];\n\n" " return (\n" " <>\n" " <ul>\n" " return (\n" " <li key={currentIndex}>\n" " <img\n" " src={currentImage.url}\n" " alt={currentImage.alt}\n" " width={currentImage.zahl}\n" " style={{ border: `4px solid ${borderColor}` }}\n" " />\n" " <p>{currentImage.alt}</p>\n" " <small>{currentImage.datum}</small>\n" " </li>\n" " );\n" " </ul>\n" " <button onClick={() => setCurrentIndex(currentIndex + 1)}>\n" " Nächstes Bild\n" " </button>\n" " <button onClick={() => setCurrentIndex(currentIndex - 1)}>\n" " Vorheriges Bild\n" " </button>\n" " </>\n" " );\n" "}\n\n" "//++++++++++ main.jsx +++++++++++++++++++\n\n" "import { StrictMode } from 'react'\n" "import { createRoot } from 'react-dom/client'\n" "import App from './App.jsx'\n\n" "createRoot(document.getElementById('root')).render(\n" " <StrictMode>\n" " <App />\n" " </StrictMode>,\n" ")\n\n\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html