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# Rust SmartDefault
Custom derive for automatically implementing the `Default` trait with customized default values:
```rust
use smart_default::SmartDefault;
#[derive(SmartDefault)]
enum Foo {
Bar,
#[default]
Baz {
#[default = 12]
a: i32,
b: i32,
#[default(Some(Default::default()))]
c: Option<i32>,
#[default(_code = "vec![1, 2, 3]")]
d: Vec<u32>,
#[default = "four"]
e: String,
},
Qux(i32),
}
assert!(Foo::default() == Foo::Baz {
a: 12,
b: 0,
c: Some(0),
d: vec![1, 2, 3],
e: "four".to_owned(),
});
```
Requires Rust 1.30+ (for non-string values in attributes)