Programming in Rust is really not like being in an abusive relationship. The compiler is trying to help out as much as possible, especially since rustc has the best error messages in the world.
Rust's error messages are one of a kind. There no other compiler which comes even close.
As a side note, i used latex lately, it's error messages are horrendous. What a nightmare to figure out what's wrong by inspecting the error.
Generally good, but man do I hate how any error in my async function causes every recursive call site to generate an error about how the Future is no longer Send and Sync. Literally an entire console scrollback of errors with the actual syntax error buried somewhere in the middle.
In this case, the first two errors are clear. The next 3 provide multiple, redundant context blocks. The upshot is that this simple example results in rustc printing 11 lines of useful error messages and 86 lines of useless messages. Add to that the fact that the useful error messages need not be at the top or bottom of the error list, they can be anywhere inside of it, depending on the declaration order.
We do spend a lot of time trying to silence errors that are irrelevant. We also get a lot of complaints when fixing a single error produces a wave of new errors that were hidden due to failures in earlier stages. It's a balancing act.
Also, specific errors are verbose in order to give people a fighting chance to fix their issue. An error that is too verbose is annoying. An error that is too terse will leave users in the cold as to what the problem was. It's yet another balancing act.
I filed https://github.com/rust-lang/rust/issues/117233 for you. Could I ask you why you didn't consider doing so when you first encountered this problem?
Edit: good news, from the next stable onwards the issue you saw no longer reproduces. You only get the parse errors with your case. https://play.rust-lang.org/?version=beta&mode=debug&edition=...
Thanks for looking into it. I have a filed a bug against Rust before, but that was a clear bug, not a poor error message. Remember, the only time a user sees something like this is when they are trying to do something else. The only reason I looked into it just now is because you explicitly asked.
My main gripe is that I still don't fully comprehend lifetimes and the compiler can't really help me every time, because it (understandably) errs on the side of caution.
I'm not sure any compiler, even one "designed for diagnostics," can gather the "necessary metadata" from inside my brain based on my original intentions. If the compiler could unambiguously interpret what I meant to write, it wouldn't have needed to fail with a compilation error in the first place. Whenever I see something like "perhaps" or "maybe" in a compilation error, the information just didn't exist anywhere the compiler could possibly get to, and it's just a suggestion based on common mistakes.