mirror of https://github.com/rust-lang/rust
34 lines
749 B
Rust
34 lines
749 B
Rust
#![feature(generic_const_exprs)]
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#![allow(incomplete_features)]
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pub struct ConstCheck<const CHECK: bool>;
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pub trait True {}
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impl True for ConstCheck<true> {}
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pub trait OrdesDec {
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type Newlen;
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type Output;
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fn pop(self) -> (Self::Newlen, Self::Output);
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}
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impl<T, const N: usize> OrdesDec for [T; N]
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where
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ConstCheck<{N > 1}>: True,
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[T; N - 1]: Sized,
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{
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type Newlen = [T; N - 1];
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type Output = T;
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fn pop(self) -> (Self::Newlen, Self::Output) {
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let mut iter = IntoIter::new(self);
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//~^ ERROR: failed to resolve: use of undeclared type `IntoIter`
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let end = iter.next_back().unwrap();
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let new = [(); N - 1].map(move |()| iter.next().unwrap());
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(new, end)
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}
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}
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fn main() {}
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