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I disagree with this. Stack traces are a lazy way to handle errors. They are useful only to the developer of an application for logic errors and bugs in the program. That is their one usecase and are very handy at that usecase.

For instance the very stack trace he gives us:

Traceback (most recent call last):
  File "/home/piku/.piku/envs/wikdict/lib/python3.11/site-packages/flask/app.py", line 1511, in wsgi_app
    response = self.full_dispatch_request()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/piku/.piku/envs/wikdict/lib/python3.11/site-packages/flask/app.py", line 919, in full_dispatch_request
    rv = self.handle_user_exception(e)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/piku/.piku/envs/wikdict/lib/python3.11/site-packages/flask/app.py", line 917, in full_dispatch_request
    rv = self.dispatch_request()
         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/piku/.piku/envs/wikdict/lib/python3.11/site-packages/flask/app.py", line 902, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)  # type: ignore[no-any-return]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/piku/.piku/apps/wikdict/wikdict_web/lookup.py", line 119, in lookup
    if r := get_combined_result(lang, other_lang, query):
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/piku/.piku/apps/wikdict/wikdict_web/lookup.py", line 91, in get_combined_result
    conn = get_conn(lang + "-" + other_lang)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/piku/.piku/apps/wikdict/wikdict_web/base.py", line 103, in get_conn
    raise sqlite3.OperationalError(
sqlite3.OperationalError: Database file "/home/piku/.piku/data/wikdict/dict/en-ko.sqlite3" does not exist

Assuming that is related to a user input this could just be

Error: Database file "/home/piku/.piku/data/wikdict/dict/en-ko.sqlite3" does not exist.

Even better to give suggestions on how the user might want to fix that problem. Everything else in that stack trace is useless noise that looks scary and takes far more time to parse and get the useful into to users of the program. Stacktraces are just as bad as not adding context to input/environmental errors, maybe only marginally better for the developer. But no user should EVER see a stacktrace and IMO any stacktrace seen should indicate a bug in the application. They are a developers tool, not a way to show users an error message.

Don't be lazy and add context and print out your errormessages in a way that is useful to the users of your application. A stacktrace is not that.

And on the side of stacktraces, they can be more noisy then necessary even for a developer. Here span traces can be useful to find the source of an error without needing to print out the current stack trace which is often vastly less useful in async contexts or other things that are not strictly a straight forward nested call stack.