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"wald493#2", flags=re.MULTILINE) test_str = ("\n" "//zeigt nur 1nen Eintrag an\n\n" "export default function SchuelerEintrag({Schueler, onDelete, onEdit}){\n\n\n\n" " return(\n\n" " <div>\n" " <br></br>\n" " <h1>Name: {Schueler.name}</h1>\n" " <p>Money: {Schueler.money}</p>\n\n" " <button type = \"button\" className=\"bg-red-500 py-2 px-4 hover:bg-red-400\" onClick={() => onDelete(Schueler.id)}>\n" " Delete\n" " </button>\n\n" " <button type =\"button\" className=\"bg-yellow-500 py-2 px-4 hover:bg-red-400\" onClick={() => onEdit(Schueler)}>\n" " Edit\n\n" " </button>\n\n" " \n\n" " </div>\n\n\n\n" " )\n\n" "//SchülerForm\n\n" "import { Sumana } from \"next/font/google\";\n" "import { useForm, Controller } from \"react-hook-form\";\n" "import { z } from \"zod\";\n" "import {zodResolver} from \"@hookform/resolvers/zod\"\n" "import { useEffect } from \"react\";\n\n\n" "const SchuelerSchema = z.object({\n" " name: z.string().min(1, \"Name ist zu kurz\"),\n" " money: z.coerce.number({invalid_type_error: \"muss eine Zahl sein\"}).gt(0, \"Zahl muss größer als 0 sein\").int(\"muss eine ganze Zahl sein\") \n" "})\n\n" "try{\n\n" "const result = SchuelerSchema.parse({name: \"\"})\n\n\n\n" "} catch(error){\n\n\n" "console.log(error.issues)\n\n" "}\n\n" "export default function SchuelerForm ({onSubmit, editData}){\n" " const {\n" " control,\n" " handleSubmit,\n" " reset,\n" " formState: {errors}\n" " } = useForm({\n" " resolver: zodResolver(\n" " SchuelerSchema\n" " ),\n" " defaultValues: {\n" " name: \"\",\n" " money: 0\n" " }\n" " })\n\n" " useEffect(() => {\n\n" " if(editData){\n" " reset(editData)\n" " }else{\n" " reset({name: \"\", money: 0})\n" " }\n\n" " }, [editData, reset])\n\n" " const submitHandler = (data) => {\n" " onSubmit(data);\n" " reset( {name: \"\", money: 0});\n" " }\n" " return(\n\n" " <div>\n" " <form \n" " onSubmit={handleSubmit(submitHandler)}\n" " >\n" " <div>\n" " <label>\n" " name: \n" " </label>\n\n" " \n\n" " <Controller\n" " name=\"name\"\n" " control={control}\n" " render={({ field })=> (\n" " <input className=\"bg-amber-300 text-black\"\n" " {...field}\n" " type = \"text\"\n" " placeholder=\"Mustername\"\n" " />\n" " )}\n" " /> \n\n" " </div>\n\n" " <div>\n" " <label>\n" " money:\n" " </label>\n\n" " <Controller\n" " name=\"money\"\n" " control={control}\n" " render={({field}) => (\n" " <input className=\"bg-amber-300 text-black\"\n" " {...field}\n" " type = \"number\"\n" " placeholder=\"0\"\n" " />\n" " )}\n" " />\n\n" " </div>\n\n" " <button type = \"sumbit\">\n" " Speichern\n" " </button>\n\n\n" " \n" " \n" " </form>\n\n" " <br></br>\n\n" " {\n" " errors.name && (<p>{errors.name.message}</p>)\n" " \n" " }\n\n" " {\n" " errors.money && (<p>{errors.money.message}</p>)\n" " }\n\n" " \n" "<br></br>\n\n" " </div> \n\n" " \n\n" " );\n" "}\n\n" "//SchülerListe\n\n" "import SchuelerEintrag from \"./SchuelerEintrag\"\n\n" "export default function SchuelerListe({Liste, handleDelete, handleEdit}){\n\n" " if(Liste.length == 0){\n" " return(\n" " <p>keine Einträge</p>\n" " )\n" " }\n\n" " return(\n" " <div>\n" " {\n" " Liste.map((Eintrag) => (<SchuelerEintrag Schueler={Eintrag} onDelete={handleDelete} onEdit={handleEdit} key = {Eintrag.id}/>))\n" " }\n" " </div>\n" " )\n\n" " \n" "}\n\n" "//page.js\n\n" "import Image from \"next/image\";\n" "import SchuelerForm from \"./components/SchuelerForm\";\n" "import SchuelerListe from \"./components/SchuelerListe\";\n\n" "import { useState } from \"react\";\n\n\n" "export default function Home() {\n\n" " const [SchuelerEinträge, setSchuelerEinträge] = useState([]);\n" " const [editData, setEditData] = useState(null);\n\n" " const addItem = (data) => { \n" " \n" " if(editData){\n" " setSchuelerEinträge((prev) => prev.map((s)=>(s.id === editData.id ? {...data, id: editData.id} : s) ) )\n" " setEditData(null)\n" " } else{\n" " setSchuelerEinträge((prev)=> [...prev, {...data, id: Date.now()}])\n" " }\n\n" " \n\n\n" " }\n\n" " const handleEdit = (Schueler) => {\n" " setEditData(Schueler)\n" " }\n\n\n" " const deleteItem = (id) => {\n" " setSchuelerEinträge((prev) => prev.filter((Eintrag) => Eintrag.id != id))\n" " } \n\n" " \n" " return (\n" " <div>\n" " <SchuelerForm onSubmit={addItem} editData={editData}/>\n" " <SchuelerListe Liste={SchuelerEinträge} handleDelete={deleteItem} handleEdit={handleEdit}/>\n" " </div>\n" " );\n" "}\n\n\n\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