3 ms·

Nah man. They could make checked exceptions less boiler platey. Simple things like Swift’s try! Or try?, and making the try construct an expression would go a l

by vips7L 11mo ago

Nah man. They could make checked exceptions less boiler platey. Simple things like Swift’s try! Or try?, and making the try construct an expression would go a long way to increase checked error usage and therefore correctness. We don’t even need to solve the lambda problem. We just need to make it easy to deal with checked exceptions. Right now you have a minimum 5 lines of boiler plate to escape them.

gf000 11mo ago
Making it an expression would indeed by nice - I do like that in Kotlin, though it's still not particularly short there (but given that there are not really checked throws there, it's easy to just have a lambda for that). I believe there was a proposal to incorporate it into the switch expression? That may make it slightly too complex though, with null handling and pattern matching.
- vips7L 11mo ago
  Yes there was a proposal by Brian to make it into a switch expression: https://news.ycombinator.com/item?id=40088719 https://news.ycombinator.com/item?id=40088719, though that draft is already 1.5 years old and I don't expect it to be delivered anytime soon. It would alleviate some pain, but I really think we need something like try! to escape the compiler when some errors aren't possible: A a; try { a = someThrowingFn(); } catch (AException ex) { throw new IllegalStateException(ex); // not possible } becomes var a = try! someThrowingFn(); or with Brian's proposal: var a = switch (someThrowingFn()) { case A anA -> anA; case throws AException ex -> throw new IllegalStateException(ex); } ...still a bit verbose and funky You should check out Kotlin's proposal for error unions, I think it's pretty good and prevents a lot of boiler plate associated with results/exceptions: https://github.com/Kotlin/KEEP/blob/main/proposals/KEEP-0441-rich-errors-motivation.md https://github.com/Kotlin/KEEP/blob/main/proposals/KEEP-0441.... They propose a similar construct to try! with !! like they have for nullable types.

by vips7L 11mo ago

gf000 11mo ago

Making it an expression would indeed by nice - I do like that in Kotlin, though it's still not particularly short there (but given that there are not really checked throws there, it's easy to just have a lambda for that). I believe there was a proposal to incorporate it into the switch expression? That may make it slightly too complex though, with null handling and pattern matching.

vips7L 11mo ago
Yes there was a proposal by Brian to make it into a switch expression: https://news.ycombinator.com/item?id=40088719 https://news.ycombinator.com/item?id=40088719, though that draft is already 1.5 years old and I don't expect it to be delivered anytime soon. It would alleviate some pain, but I really think we need something like try! to escape the compiler when some errors aren't possible: A a; try { a = someThrowingFn(); } catch (AException ex) { throw new IllegalStateException(ex); // not possible } becomes var a = try! someThrowingFn(); or with Brian's proposal: var a = switch (someThrowingFn()) { case A anA -> anA; case throws AException ex -> throw new IllegalStateException(ex); } ...still a bit verbose and funky You should check out Kotlin's proposal for error unions, I think it's pretty good and prevents a lot of boiler plate associated with results/exceptions: https://github.com/Kotlin/KEEP/blob/main/proposals/KEEP-0441-rich-errors-motivation.md https://github.com/Kotlin/KEEP/blob/main/proposals/KEEP-0441.... They propose a similar construct to try! with !! like they have for nullable types.