Comment by nemothekid | Hacker News Reader

Comment by nemothekid | Hacker News Reader

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If I am in the business of writing robust code; then "assuming all functions can throw" means at the very least forcing every function call to be surrounded by a try/catch block? It almost always make sense to handle an error locally if you can; for example if I want to retry the operation (let's say I'm writing a distributed database client), it may make sense for me to retry another node rather than unwinding to the application level that has now lost all context.

>A function that has no possibility of error is so uninteresting that focusing on that is the wrong thing.

I spend a lot of time debugging errors in code that has 0% chance of failing. It tends to involve a lot of matrix math. This isn't something you can say is universally true especially given all the hype around AI now.

> It almost always make sense to handle an error locally if you can

This is highly presumptuous. I have written many programs that did not need to handle errors locally, and so exception handlers were only at the very top level (or, actually, just below the top-level usually - but the point is that there were generally few and I had flexibility to decide where to put them). Perhaps you and I write very different applications. But the fact remains that the "almost always" in your statement doesn't hold.

Alternatively line of reasoning: if this was always true then there would be little point to Rust's ? as it would be so rarely used.

> It almost always make sense to handle an error locally if you can

Yes, but “if you can” does a lot of heavy lifting here. In most cases you can’t, and this is when Rust’s ? is used.

> If I am in the business of writing robust code; then "assuming all functions can throw" means at the very least forcing every function call to be surrounded by a try/catch block?

No, absolutely not! You only care about errors where you can retry/ignore or log and terminate so you only have try/catch in those areas. So maybe one or two.

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