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Comment by marmaduke | Hacker News Reader

yep! there was a sort of epiphany for me, the first I wrote Java, from Python, when I realized that I can be sure that my code could handle anything the callee could throw at it.

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There are still plenty of exceptions that are unchecked, i.e. subtypes of RuntimeException, which do not have to be declared on the callee. As well as people who think it's a good idea to throw instances of Exception and just tack a "throws Exception" on their methods.

Right — that's a failing of Java the language; not the concept of checked exceptions. At least one problem with Java's exception model that Zig does not have is that some exceptions are "unchecked."

The 'failing' of checked exceptions comes from essentially being forced to couple the type signatures of your methods' successful results with their error results. A more explicit way to do this is with Optional/Either types, and now you don't need the checked exceptions feature nor need to get people to remember to check for a global errno or some other data convention like an empty string / null. There's a lot of boilerplate though, just like with checked exceptions.

I prefer a more decoupled/late-binding approach to error handling; so far Common Lisp does it the best I've seen.[0] The key insight CL people had was that often in the face of an error, you need help from somewhere away from your local context to figure out how to resolve it, but then for many cases, you want to return back to where the error has occurred and take the resolution path with your local context. In other languages that automatically unwind the stack to the exception handler, it's too late.

[0] http://www.nhplace.com/kent/Papers/Condition-Handling-2001.h...

Zig has system-exit, which is strictly less useful than unchecked exceptions, so Zig certainly has the same problem.

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