derive-ex

Improved version of the macro to implement the traits defined in the standard library.

Documentation

See #[derive_ex] documentation for details.

Differences from standard derive macros

• A trait bound that is automatically generated is smarter.
• You can specify trait bound manually.
• You can specify default values for each field.
• You can specify comparison method for each field.
• You can specify ignored field with the derivation of Debug.
• Support derive Clone::clone_from.
• Support derive operators. (Add, AddAssign, Not, Deref, etc.)

Supported traits

• Copy
• Clone
• Debug
• Default
• Ord, PartialOrd, Eq, PartialEq, Hash
• operators
  • Add-like (Add, Sub, Mul, Shl, etc.)
  • AddAssign-like (AddAssign, SubAssign, MulAssign, ShlAssign, etc.)
  • Not-like (Not, Neg)
  • Deref, DerefMut

Unsupported traits

The following traits are not supported as more suitable crates exist.

trait	crate
Display, FromStr	parse-display
Error	thiserror

Install

Add this to your Cargo.toml:

[dependencies]
derive-ex = "0.1.7"

Example

use derive_ex::derive_ex;

#[derive(Eq, PartialEq, Debug)]
#[derive_ex(Add, AddAssign, Clone, Default)]
struct X {
    #[default(10)]
    a: u32,
}
assert_eq!(X { a: 1 } + X { a: 2 }, X { a: 3 });
assert_eq!(X::default(), X { a: 10 });

#[derive(Eq, PartialEq, Debug)]
#[derive_ex(Clone, Default)]
enum Y {
    A,
    #[default]
    B,
}
assert_eq!(Y::default(), Y::B);

License

This project is dual licensed under Apache-2.0/MIT. See the two LICENSE-* files for details.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.