Use `?` instead of `try!`

[janhohenheim]

RFC

[TrionProg]

Hello. Thank you for RFC, but I guess, you've read documentation not careful =). Doc says:
This macro looks like standard try!() macro but it gets information where the error has been occurred. ? = try! = match $expr { Ok (ok) => ok, Err(e) => Err(e) }. Am I right? I will be happy if ? will call $error( error_info!(), Box::new(e) ), but this future is not supported, am I right?

About catch I hear for the first time. This is seriously funny. Hmm, I think, I should add it into example, but I've never needed catch.

[janhohenheim]

As you can see from the actual PR, the the ? operator is de facto equivalent with try! and has replaced the latter in the rustc source itself.

[TrionProg]

Can it get information, where this error has been occurred?

Note:I use ? only with errors, that already contain this information(but then I get ErrorInfo of impl_from_error!(), this is also not good =( ). So I think, ? should get this information!