25 lines
541 B
Rust
25 lines
541 B
Rust
#![allow(dead_code)]
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use std::ops::Add;
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use darling::{FromDeriveInput, FromMeta};
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#[derive(Debug, Clone, FromMeta)]
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#[darling(bound = "T: FromMeta + Add")]
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struct Wrapper<T>(pub T);
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impl<T: Add> Add for Wrapper<T> {
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type Output = Wrapper<<T as Add>::Output>;
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fn add(self, rhs: Self) -> Wrapper<<T as Add>::Output> {
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Wrapper(self.0 + rhs.0)
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}
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}
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#[derive(Debug, FromDeriveInput)]
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#[darling(attributes(hello), bound = "Wrapper<T>: Add, T: FromMeta")]
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struct Foo<T> {
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lorem: Wrapper<T>,
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}
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#[test]
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fn expansion() {}
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