smart-default 0.3.0

Rust custom-derive macro for Default with more control on the fields

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Rust SmartDefault

Custom derive for automatically implementing the Default trait with customized default values:

#[macro_use]
extern crate smart_default;

#[derive(SmartDefault)]
enum Foo {
    Bar,
    #[default]
    Baz {
        #[default = 12]
        a: i32,
        b: i32,
        #[default(Some(Default::default()))]
        c: Option<i32>
    },
    Qux(i32),
}

assert!(Foo::default() == Foo::Baz { a: 12, b: 0, c: Some(0) });

Requires Rust 1.30+ (for non-string values in attributes)