public constructor(data: T) {

    _.assign(this, _.omit(data, [
        "table",
        "id",
        "PartitionKey",
        "RowKey",
    ]));
}

export abstract class Base<T extends EntityData> implements Storage.AbstractEntity & T {
...

export class AuthorFact extends Base<Author> {

    public get RowKey() { return (this as any).id }
}