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              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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