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376 points turrini | 2 comments | | HN request time: 0.001s | 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. rkharsan64 ◴[] No.42149226[source]
From my (super limited) experience, debuggers shine when:

- You're using a dynamically typed language.

Something like Rust can eliminate most bugs that come from incorrect data types. For me, a lot of bugs used to come from types that were different from what I expect.

- It is super easy to run your program with a debugger attached.

If your code needs to run on a K8s cluster or a dedicated test machine instead of locally, logs are much easier to get hold of than a remote debug session. Some people aren't even aware that they can attach a debugger to a computer over the network, or inside a Docker container.

- Your environment.

If you don't use an IDE that supports a debugger, it's another friction point. I'm not sure if Vim has something similar to, say, PyCharm's debugger.

Similarly, if you're a junior, and you reach out to a senior and they tell you to debug using logs, you probably will never switch to using a debugger yourself.

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2. mark_undoio ◴[] No.42150570[source]
If you use a time travel debugger (rr-project.org, undo.io - where I work, or Microsoft's WinTTD) you can generally just record an application to a file and debug it (with full fidelity) somewhere else.

And you don't need a full debugger setup on the target machine, just the recorder binary.

Gives you the possibility to have a proper debug experience without having to set up debugging that somehow works in a live k8s pod, or connects through special firewall holes or somesuch.