Non-additive feature behavior

[dtolnay]

This code works:

use static_assertions::const_assert;

fn main() {
    const_assert!(false != true);
}

until any other crate in my dependency graph enables static_assertions' "nightly" feature. Then it breaks my crate's formerly working code. This is not good behavior for a cargo feature. Code that works without a feature must also work with the feature, otherwise you end up with libraries that work in isolation but can't be combined together in one dependency graph.

[nvzqz]

🤦‍♂️ wow I had never considered this, thank you for letting me know. I suppose the only real solution is to remove the const _ bit until it becomes stabilized in 1.37 (rust-lang/rust#61347).

[nvzqz]

Closed with the release of 1.0. 😄