[Feature] target rustc stable

[JohnLih]

Compiling tarpc-plugins v0.1.0 (https://github.com/google/tarpc#f9ff2c4e)
error[E0554]: #[feature] may not be used on the stable release channel
--> ~/.cargo/git/checkouts/tarpc-87655b19c07c6cd1/f9ff2c4/src/plugins/src/lib.rs:1:1
|
1 | #![feature(plugin_registrar, rustc_private)]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error

error: Could not compile tarpc-plugins.

rustc version : rustc 1.15.1 (021bd294c 2017-02-08)
cargo version : cargo 0.16.0-nightly (6e0c18c 2017-01-27)
OS version : macOS Sierra 10.12.3

[tikue]

Sorry about that! tarpc currently only works on nightly. We should probably have a better disclaimer in the readme.

I expect tarpc will work on stable sometime this year; we're basically waiting on the forthcoming procedural macros 2.0 overhaul. We could also add build script support or something like that, there just hasn't been anyone asking for it.

[mark-i-m]

A subset of macros 2.0 is being stabilized now (in fact, it is already stable on nightly IIUC). Do you know if this subset is sufficient to move tarpc to stable? https://internals.rust-lang.org/t/help-stabilize-a-subset-of-macros-2-0/7252

[tikue]

I don't believe so, because the subset being stabilized does not allow you to reexport a proc macro from another crate. :( I'm working on some pretty big updates for async/await and futures 0.3, though. That might land in the next few weeks.

[chefsalim]

Wondering if there is any update on this?

[tikue]

Given that #199 uses the std futures API and async/await, I think it's safe to say targeting stable is out of reach for the foreseeable future.

[tikue]

#199 does remove the use of rustc plugins (!!) so we're definitely moving closer to this. However, I still don't think futures/async/await will be stable very soon.

[mark-i-m]

I'm not sure about that. A lot of work is going into the edition 2018 stuff, so almost everything else is paused, but async/await and networking are high priority, and I suspect that they will resume work on them pretty soon after the edition ships. My guess is that they stabilize some time next year.

[tikue]

Yeah :) whenever they're stable, I believe I can target stable.

[vorot93]

See #242