alt Hacker NewsReminds me of the best saying I ever got from my CS professor. She would make us first write out our code and answer the question, "What will the output be?" before we were allowed to run it.
"If you don't know what you want your code to do, the computer sure as heck won't know either." I keep this with me today. Before I run my code for the first time or turn on my hardware for the first time, I ask myself, "What _exactly_ am I expecting to see here?" and if I can't answer that it makes me take a closer and more adversarial look at my own output before running it.
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I'm not 100% convinced, while iterating fast on an early prototype, what's wrong with legitimately not knowing what e.g. the data structure will end up looking? Just let it run, check debugger/stdout/localhost page and adjust: "Oh, right, the entries are missing canonical IDs, but at the same time there are already all the comments in them, forgot they would be there – neat". What's wrong with that? Especially at uni, when working on low-stakes problems.
This is a restatement of the old wisdom that to safely use a tool you must be 10% smarter than it is." Or stated differently, you must be "ahead" of the tool (capable of accurately modeling and predicting the outcome), not "behind" (only reacting). TDD is kind of an outgrowth of it. I've lived by the wisdom, but admit that for me there is a lot of fun in the act of verifying hypotheses in the course of development, even in the "test case gap" when you're writing the lines of code that don't make a difference in terms of making a long term test case go from red to green, or doing other exploratory work where the totality of behavior is not well charted. Those times are the best. "Moodily scowling at the computer screen again," has been a status update from chilluns on what I'm doing more times than I like to admit.
Isn't this the whole idea of TDD? Write your assertions, then write the code the fulfill it.