[pimeys]

That's nothing!

      |
  212 | /     fn call(&self, payload: Self::Request) -> Self::Future {
  213 | |         let request = self.create_request(payload);
  214 | |
  215 | |         let work = async_block! {
  ...   |
  254 | |         FutureResponse(Box::new(work))
  255 | |     }
      | |_____^
  note: ...so that the type `impl futures::__rt::MyFuture<<[generator@src/client.rs:215:20: 252:10 self:&client::Client,

request:hyper::Request for<'r> {futures::Async<futures::__rt::Mu>, (), fn(std::result::Result<hyper::Response, error::Error>) -> std::result::Result<<std::result::Result<hyper::Response, error::Error> as std::ops::Try>::Ok, <std::result::Result<hyper::Response, error::Error> as std::ops::Try>::Error> {<std::result::Result<hyper::Response, error::Error> as std::ops::Try>::into_result}, futures::MapErr<hyper::client::FutureResponse, [closure@src/client.rs:217:59: 217:85]>, hyper::Response, std::option::Option<std::string::String>, &'r hyper::Response, hyper::StatusCode, fn(std::result::Result<hyper::Chunk, error::Error>) -> std::result::Result<<std::result::Result<hyper::Chunk, error::Error> as std::ops::Try>::Ok, <std::result::Result<hyper::Chunk, error::Error> as std::ops::Try>::Error> {<std::result::Result<hyper::Chunk, error::Error> as std::ops::Try>::into_result}, futures::stream::Concat2<futures::stream::MapErr<hyper::Body, [closure@src/client.rs:234:49: 234:75]>>}] as std::ops::Generator>::Return>` will meet its required lifetime bounds

[vardump]

I see. Rust is aiming to be closer and closer to C++ every day!

Anyways, I think it has still long way to go to match the length of even common C++ template related error messages...

[coldtea]

>I see. Rust is aiming to be closer and closer to C++ every day!

Or you know, it's aiming nothing of the short, and this is early, still unsorted, behavior, while the language has been simplifying things (e.g. the early sigils and lots of other stuff), and plans even more simplification and friendliness.

https://jvns.ca/blog/2018/01/13/rust-in-2018--way-easier-to-...

https://blog.rust-lang.org/2018/03/12/roadmap.html

[pimeys]

I've definitely seen much worse with C++. These kind of errors you get though when you use Tokio and combine many different futures together, the future wanting to have static lifetimes and me using a reference to self inside an async block, hopefully solved this year.

[thowawayburnout]

I have found while the C++ error messes can be very long, its surprisingly often in the first line of the error message that you see the problem.

[pjmlp]

Also since clang, at least using recent versions of clang, gcc and VC++ they use heuristics to try to present some kind of meaningful message.

And latest C++14 and C++17 changes also help library writers to error check the type parameters.

Of course those that have to use other compilers still need to face the sea of incomprehensible error messages.

And in any case, better stay away from template meta-programming libraries, at least until modules and concepts eventually land.