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interface Person {
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  name: string
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}
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type DB = Record<string, Person>
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const db: DB = {
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  bob: {
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    name: 'Bob',
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  },
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  jeff: {
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    name: 'Jeff',
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  },
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}
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const alwaysDefinedHandler: ProxyHandler<DB> = {
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  get(target, prop, receiver) {
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    const user = db[prop as string]
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    if (!user) {
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      db[prop as string] = {
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        name: prop as string,
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      }
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      return db[prop as string]
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    }
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    return user
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  },
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}
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const insertIfNotFoundDb = new Proxy<DB>(db, alwaysDefinedHandler)
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console.log(insertIfNotFoundDb.bob)
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console.log(db)
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// smith is not in the database, but the act of accessing it through a proxy will create the person
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// based on the logic we have defined in the proxy
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console.log(insertIfNotFoundDb.smith)
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console.log(db)
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// @ts-expect-error
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console.log(insertIfNotFoundDb[new Date()])
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console.log(db)