 resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years.
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> That design makes failure **implicit**. Any time you think you have a `String` you just might have a `null` instead. Should you check? Did the person giving you the value check? Maybe it will be fine? Maybe it will crash your server? I guess we will f