5 ms·

Wow, thanks for the reply. I copied the signature directly from your post and... it didn't work. I still got `user_index_handler` does not live long enough. But

by ainar-g 10y ago

Wow, thanks for the reply. I copied the signature directly from your post and... it didn't work. I still got `user_index_handler` does not live long enough. But! If I replace impl server::Handler for UserIndexHandler with impl UserIndexHandler it does compile. Removing the trait impl was another thing recommended by the Arc guy at work, he didn't know how or why it worked. Here is the code that doesn't compile with updated Postgres: https://is.gd/fjYDIG https://is.gd/fjYDIG. Which brings me to a question, how does implementing a trait prevent this code from compiling? Sorry for comparing apples to oranges again, but in Go implementing an interface is an invisible operation, that doesn't affect compilation. What's different with Rust?

steveklabnik 10y ago
I am about to go into two hours of meetings so this will have to be quick. The issue is, because this is a trait, you must conform to its signature. Which is here: https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.html https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.ht... and specifically https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.html#tymethod.handle https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.ht... So yeah, my idea won't work, because those types conflict. > Removing the trait impl was another thing recommended by the Arc guy at work, he didn't know how or why it worked. I'm surprised it works on first glance, as I was assuming that you were implementing the trait for a reason, not just because. If you don't need the trait, then yeah, it's much easier. > What's different with Rust? See my StackExchange link elsewhere in the thread for a summary. I'll maybe poke at this after my meetings, or maybe tomorrow. We'll see how amped I am for coding after all that ;)
- ainar-g 10y ago
  Okay, thank you again for your time!
  - steveklabnik 10y ago
    Ah! I understand now. Handlers aren't meant to be nested like this. That is, it's always going to break this way, because the handler needs to live as long as the request and response, so creating a sub-handler is not ever going to live long enough. So yes, the solution is to not implement Handler for your UserIndexHandler; then you can just call it. I bet there's something larger you could do as well, but I don't have enough experience with this interface to give good advice. Hyper's undergoing a huge docs drive for 0.11; I'm sure that'll help.
    - ainar-g 10y ago
      Yeah, I figured that out as well, but thank you for finding the time to analyse the code and write an answer. I appreciate it and may be on my fourth attempt at actually learning Rust :)
      - steveklabnik 10y ago
        No problem. :)

by ainar-g 10y ago

steveklabnik 10y ago

I am about to go into two hours of meetings so this will have to be quick. The issue is, because this is a trait, you must conform to its signature. Which is here: https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.html https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.ht... and specifically https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.html#tymethod.handle https://hyper.rs/hyper/v0.10.0/hyper/server/trait.Handler.ht... So yeah, my idea won't work, because those types conflict. > Removing the trait impl was another thing recommended by the Arc guy at work, he didn't know how or why it worked. I'm surprised it works on first glance, as I was assuming that you were implementing the trait for a reason, not just because. If you don't need the trait, then yeah, it's much easier. > What's different with Rust? See my StackExchange link elsewhere in the thread for a summary. I'll maybe poke at this after my meetings, or maybe tomorrow. We'll see how amped I am for coding after all that ;)

ainar-g 10y ago
Okay, thank you again for your time!
- steveklabnik 10y ago
  Ah! I understand now. Handlers aren't meant to be nested like this. That is, it's always going to break this way, because the handler needs to live as long as the request and response, so creating a sub-handler is not ever going to live long enough. So yes, the solution is to not implement Handler for your UserIndexHandler; then you can just call it. I bet there's something larger you could do as well, but I don't have enough experience with this interface to give good advice. Hyper's undergoing a huge docs drive for 0.11; I'm sure that'll help.
  - ainar-g 10y ago
    Yeah, I figured that out as well, but thank you for finding the time to analyse the code and write an answer. I appreciate it and may be on my fourth attempt at actually learning Rust :)
    - steveklabnik 10y ago
      No problem. :)