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Comment by esistgut | Hacker News Reader

I don't like the debugging workflow described in the linked article "Debugging techniques in Elixir", it reminds me of DDD: a separate tool not integrated with my main development environment and requiring extra manual steps. I tested both the Jetbrains plugin and the vscode extension, both failed (unsupported versions, bugs, etc...). To elixir users: what do you think about the state of debugging tools? What is your workflow?

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Well you have the basic IO.inspect/2 that you can use for "printf" debugging. It works really well with the pipe operator because it prints the structure and returns the structure itself not the string representation, so you can do stuff like:

some_function() |> IO.inspect |> some_other_function

Also with Elixir 1.5 (OTP 20) you can set breakpoints easily from within IEx.

There is also IEx.pry where you can set the "breakpoint" in the code itself.

There is the observer tool where you can inspect each process and see numerous information that can be useful. When in IEx just type :observer.start and try it out yourself.

I suggest reading Designing for Scalability with Erlang/OTP, particularly the chapter about Erlang/Elixir tracing facilities that can be really useful when debugging live production systems.

Compared to other languages, I find that I need less debugging in general. When I need debugging it's usually because of libraries/external dependencies with weird behavior, but sine everything is a function, it's easier to figure out what's wrong and where since you can call anything as a function in iEX.

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