creusot_contracts/std/iter/
copied.rs

1#[cfg(creusot)]
2use crate::resolve::structural_resolve;
3use crate::{invariant::*, prelude::*};
4use std::iter::Copied;
5
6pub trait CopiedExt<I> {
7    #[logic]
8    fn iter(self) -> I;
9}
10
11impl<I> CopiedExt<I> for Copied<I> {
12    #[logic(opaque)]
13    fn iter(self) -> I {
14        dead
15    }
16}
17
18impl<I> Invariant for Copied<I> {
19    #[logic(prophetic, open, inline)]
20    fn invariant(self) -> bool {
21        inv(self.iter())
22    }
23}
24
25impl<I> Resolve for Copied<I> {
26    #[logic(open, prophetic, inline)]
27    fn resolve(self) -> bool {
28        resolve(self.iter())
29    }
30
31    #[trusted]
32    #[logic(prophetic)]
33    #[requires(structural_resolve(self))]
34    #[ensures(self.resolve())]
35    fn resolve_coherence(self) {}
36}
37
38impl<'a, I, T: 'a> IteratorSpec for Copied<I>
39where
40    I: IteratorSpec<Item = &'a T>,
41    T: Copy,
42{
43    #[logic(open, prophetic)]
44    fn completed(&mut self) -> bool {
45        pearlite! {
46            exists<inner: &mut _> *inner == self.iter() && ^inner == (^self).iter() && inner.completed()
47        }
48    }
49
50    #[logic(open, prophetic)]
51    fn produces(self, visited: Seq<Self::Item>, o: Self) -> bool {
52        pearlite! {
53            exists<s: Seq<&'a T>>
54                   self.iter().produces(s, o.iter())
55                && visited.len() == s.len()
56                && forall<i> 0 <= i && i < s.len() ==> visited[i] == *s[i]
57        }
58    }
59
60    #[logic(law)]
61    #[ensures(self.produces(Seq::empty(), self))]
62    fn produces_refl(self) {}
63
64    #[logic(law)]
65    #[requires(a.produces(ab, b))]
66    #[requires(b.produces(bc, c))]
67    #[ensures(a.produces(ab.concat(bc), c))]
68    fn produces_trans(a: Self, ab: Seq<Self::Item>, b: Self, bc: Seq<Self::Item>, c: Self) {}
69}