THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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The "." is called the "dereference operator". In addition, there is a a "safe dereference operator", "?.", which works the same as "." except that it allows any of the properties to be null. When reading, a null short-circuits the expression (which returns null). When writing to a property, an intermediate null value will cause the value to be discarded without error.
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