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