41 lines
823 B
Rust
41 lines
823 B
Rust
#![feature(extern_types)]
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extern "Rust" {
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type OpaqueListContents;
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}
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pub struct ListS<T> {
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len: usize,
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data: [T; 0],
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opaque: OpaqueListContents,
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}
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pub struct Interned<'a, T>(&'a T);
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impl<'a, T> Clone for Interned<'a, T> {
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fn clone(&self) -> Self {
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*self
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}
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}
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impl<'a, T> Copy for Interned<'a, T> {}
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pub struct List<'tcx, T>(Interned<'tcx, ListS<T>>);
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//~^ NOTE this field does not implement `Copy`
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//~| NOTE the `Copy` impl for `Interned<'tcx, ListS<T>>` requires that `OpaqueListContents: Sized`
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impl<'tcx, T> Clone for List<'tcx, T> {
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fn clone(&self) -> Self {
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*self
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}
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}
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impl<'tcx, T> Copy for List<'tcx, T> {}
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//~^ ERROR the trait `Copy` cannot be implemented for this type
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fn assert_is_copy<T: Copy>() {}
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fn main() {
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assert_is_copy::<List<'static, ()>>();
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}
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