With defensive programming, the main idea is that if a function is passed bad data it won’t be hurt, even if the bad data is another function’s fault. More generally, it’s the recognition that programs will be modified later on and will have problems, and that a smart developer will write their code to account for this. In this session you’ll learn how to protect yourself from the cold, cruel world of invalid data, events that can “never” happen, and other developers’ mistakes.
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