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https://github.com/rust-lang/rust
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32 lines
706 B
Rust
32 lines
706 B
Rust
#![feature(generic_const_exprs)]
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#![allow(incomplete_features, const_evaluatable_unchecked)]
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use std::marker::PhantomData;
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struct DataHolder<T> {
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item: T,
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}
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impl<T: Copy> DataHolder<T> {
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const ITEM_IS_COPY: [(); 1 - { //~ ERROR unconstrained generic constant
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trait NotCopy {
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const VALUE: bool = false;
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}
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impl<__Type: ?Sized> NotCopy for __Type {}
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struct IsCopy<__Type: ?Sized>(PhantomData<__Type>);
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impl<__Type> IsCopy<__Type>
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where
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__Type: Sized + Copy,
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{
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const VALUE: bool = true;
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}
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<IsCopy<T>>::VALUE
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} as usize] = []; //~ ERROR unconstrained generic constant
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}
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fn main() {}
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