mirror of https://github.com/rust-lang/rust
30 lines
445 B
Rust
30 lines
445 B
Rust
//@ run-pass
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use std::marker::PhantomData;
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fn main() {
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let _arr = [1; <Multiply<Five, Five>>::VAL];
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}
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trait TypeVal<T> {
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const VAL: T;
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}
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struct Five;
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impl TypeVal<usize> for Five {
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const VAL: usize = 5;
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}
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struct Multiply<N, M> {
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_n: PhantomData<N>,
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_m: PhantomData<M>,
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}
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impl<N, M> TypeVal<usize> for Multiply<N, M>
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where N: TypeVal<usize>,
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M: TypeVal<usize>,
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{
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const VAL: usize = N::VAL * M::VAL;
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}
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