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377 points turrini | 4 comments | | HN request time: 0.628s | source
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rkharsan64 ◴[] No.42146864[source]
On a general note, I would recommend any new (and experienced!) programmers to master the debugging tools of their ecosystem. I've seen countless experienced developers use printf-based debugging and waste hourse debugging something which could've been easily figured out by setting a breakpoint and stepping through your code. This is also a good way to understand code you're unfamiliar with.

This is one area where I believe a GUI tool is so much better: I can hover over variable names to view their values, expand and collapse parts of a nested structure, edit values easily, and follow execution in the same environment I write my code in.

Sure, it doesn't help much for some scenarios (one I've heard people mention is multithreaded code, where logs are better?), but for most people it's not that far from a superpower.

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mpweiher ◴[] No.42147101[source]
Interesting.

My experience is the opposite: I see developers waste hours stepping through their code a line at a time when a few judiciously placed logs (printfs() are fine, but we can do better) would have told them exactly what they needed in a jiffy.

If you have a fairly shallow bug, that is a single point in your code that always behaves incorrectly, then I find debuggers reasonably effective.

But most of the bugs that I see aren't that shallow, with code misbehaving when the context is just so and perfectly fine otherwise. In those cases, I need to see lots of different invocations and their context. The debugger is like trying to drink the information ocean I need through a straw. A mostly plugged straw.

I wonder what makes our experiences so different? Do you unit test a lot? Particularly with TDD? I am guessing that this practice means I just don't get to see a lot of the bugs that a debugger would help me with.

(And it doesn't mean I never fire up the debugger. But it is fairly rare).

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1. agumonkey ◴[] No.42147373[source]
I agree with both of you. Printf is not enough, breakpoints are not enough. The solution lies between. Ability to gather rapidly relevant information to converge on wrong states.

ps: I wish I could work on a porcelain layer to manage the breakpoints in a more logical manner. Considering a problem you'd like to create different sets of breakpoints, run various tests and gather results to reviews. With the ability to add or remove layers rapidly. It's probably not too hard to do.

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2. conradev ◴[] No.42147396[source]
I have found combining these things to be useful: breakpoints that print stuff and auto-resume the program. Allows you to attach trace points at-will without requiring a recompile or losing state.
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3. agumonkey ◴[] No.42147548[source]
Yes losing state is a killer
4. null_deref ◴[] No.42147738[source]
Yes exactly, and I'll probably say very generally that I usually use breakpoints when I am in the exploration stage of a significant state bug, and I'll usually use logging when I generally know where the bug should be but I need to pin point the exact place