Comment by rikthevik | Hacker News Reader

Comment by rikthevik | Hacker News Reader

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> The code is allowed to continue after it has logically bugged out.

I'm a big fan of asserting preconditions and making it clear that we are getting into a bad place. I would rather dig through Sentry for an AssertionError than propagate a bad state and having to fix mangled data after the fact. If the AssertionError means that we mishandled valid user input, no problem, we'll go fix it.

A few times in my career I've had to ask, "okay, how long has this bug been quietly mangling user data?" and it's not a fun place to be.

Side note: I've never understood the convention of removing asserts in production builds. It seems like removing the seatbelts from the car before the race just to save a few pounds.

> Side note: I've never understood the convention of removing asserts in production builds. It seems like removing the seatbelts from the car before the race just to save a few pounds.

Once an upon a time computers were slow and every cycle mattered. Assertions were compiled out of the build by necessity. Better a crash once in a while than the program hardly running because it was so slow.

Case in point: When I was stuck inside a "big ball of perl" codebase that heavily used assertions for method input validation, I generated a flame graph of where time was spent in the codebase and it turned out it was assertions all the way down. Since only a small percentage of inputs came from external/unvalidated sources (user input etc) it was fine to remove the vast majority of them outside of the development environment. So we turned them into no-ops in prod and had a significant performance improvement.

Wouldn’t happen to have been a big healthcare company in Boston whose assert-anything function to validate that functions were called with correct signatures was called AssertFields?

As it happens, it was at such a place exactly as you describe. Hello fellow traveler, our paths may have crossed.

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