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quorum_set/quorum/
quorum_bridge.rs

1#[cfg(doc)]
2use crate::QuorumIntersection;
3use crate::quorum::QuorumSet;
4
5/// Builds an intermediate quorum set that has [`QuorumIntersection`] with both
6/// the source and the target quorum set.
7pub trait QuorumBridge<Other>
8where
9    Self: QuorumSet,
10    Other: QuorumSet<Id = Self::Id>,
11{
12    /// Build a quorum set `X` so that `self ~ X ~ other`, where `~` is the
13    /// [`QuorumIntersection`] relation.
14    ///
15    /// Then `X` is the intermediate quorum set when changing membership from
16    /// `self` to `other`.
17    ///
18    /// E.g.(`cᵢcⱼ` is a joint of `cᵢ` and `cⱼ`, and no two distinct configs among `c₁`, `c₂`,
19    /// `c₃` have intersecting quorums):
20    /// - `c₁.bridge_to(c₁)`   returns `c₁`
21    /// - `c₁.bridge_to(c₂)`   returns `c₁c₂`
22    /// - `c₁c₂.bridge_to(c₂)` returns `c₂`
23    /// - `c₁c₂.bridge_to(c₁)` returns `c₁`
24    /// - `c₁c₂.bridge_to(c₃)` returns `c₂c₃`
25    fn bridge_to(&self, other: Other) -> Self;
26}