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376 points turrini | 1 comments | | HN request time: 0s | 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. toprerules ◴[] No.42148838[source]
I'm an OS developer and in my view using printf is like seeing only half the world at once. There's a whole world of platform specific decisions that are made at compile time and runtime that you can only see through the lens of a good assembly debugger.

You're also talking about debugging apps running comfortably in the idillic world created by the OS. It's much harder to debug foundational pieces with printf's when the program immediately panics or early printing isn't available.

In my opinion it's good to build habits that can be generalized to all sorts of software and not limit oneself to writing code in a highly structured environment where most of the work is done for you. I can trace through a program faster than someone can insert/remove printfs and recompile their program, and I don't need to think about what to print. I can look at everything at that point in time, covert data to strings, look at the stack, registers, etc. Very powerful stuff.