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