Unstable functionality in Serde

[dtolnay]

Currently unstable

• [ ] Never type https://github.com/rust-lang/rust/issues/35121
  • Serialize and Deserialize impls for !

Stabilized

• [x] Serialize and Deserialize for NonZero* https://github.com/rust-lang/rust/issues/49137
  • Stabilized in 1.0.60 #1278
• [x] Deserialize for Box\ https://github.com/rust-lang/rust/issues/40380
  • Requires CString::into_boxed_c_str
  • Stabilized in 1.0.61 #1284
• [x] Deserialize for dynamically sized Rc / Arc https://github.com/rust-lang/rust/issues/40475
  • Requires From<Box<T>> for Rc<T> / Arc<T>
  • Stabilized in 1.0.61 #1285
• [x] core::error::Error https://github.com/rust-lang/rust/issues/103765
  • Stabilized in 1.0.210 #2818

Removed

• [x] Specialization https://github.com/rust-lang/rust/issues/31844
  • The default collect_seq and collect_map used to specialize for ExactSizeIterator.
  • Removed in #1841.

[nox]

Feature zero_one just died. Can we have new versions on both 0.9 and 1.0?

[SimonSapin]

Submitted https://github.com/serde-rs/serde/pull/898 for zero_one.

[Techcable]

593bcb087de2d09960aefaccb67d5871ddf4edc8 breaks the unstable feature because you removed the nonzero feature flag which is still required by NonZeroU16 and friends.

[dtolnay]

The nonzero feature flag was removed from nightly in https://github.com/rust-lang/rust/pull/50808.

[Techcable]

Thanks so much for the clarification, I didn't realize I was using an outdated nightly!

[dtolnay]

I updated the list to reflect functionality that was stabilized in Serde 1.0.60 and 1.0.61. These are no longer behind the "unstable" cfg.

[dtolnay]

Added never_type in #1302.

[dtolnay]

Added error_in_core in #2344.

[gootorov]

Would it be appropriate to add support for Vec<T, A: Allocator>/Box<T, A: Allocator> under the unstable feature flag? If so, I can submit a PR in some near future.

[jdygert-spok]

Error in core has been stabilized. Would it be appropriate to make StdError = core::error::Error when minor >= 81?