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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              let originalObj = { x: 42, y: "Hallo" };

// Der Proxy-Hander enthält "traps", d.h. die
// Logik für das Abfangen bestimmter Operationen
const handler = {

  // Get-Trap für das Auslesen von Properties auf
  // dem Objekt, für das der Proxy als Proxy fungiert
  // "targetObj" ist das Ziel-Objekt, "property" die
  // angfragte Eigenschaft. Der Rückgabewert dieser
  // Funktion bestimmt die Antwort
  get: function (targetObj, property){
    // Angefragte Eigenschaft aus Ziel auslesen...
    let value = targetObj[property];
    // ... und manipulieren wenn es eine Zahl ist
    if(typeof value === "number"){
      value = value * 2;
    return value;


// Einen Proxy auf das Original-Objekt mit der Logik
// aus "handler" anlegen. Der Proxy verhält sich wie
// das Original-Objekt, nur die im Handler definierten
// Operationen liefern andere Ergebnisse bzw. lösen
// Nebenwirkungen aus
let proxyObj = new Proxy(originalObj, handler);

console.log(originalObj.y); // > "Hallo"
console.log(proxyObj.y);    // > "Hallo"
console.log(originalObj.x); // > 42
console.log(proxyObj.x);    // > 84 - der Proxy schlägt zu!
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