willow_data_model/groupings/
keylike.rs

1use crate::paths::*;
2
3/// A keylike value is one that can be used to uniquely identify an [Entry](https://willowprotocol.org/specs/data-model/index.html#Entry) within a [namespace](https://willowprotocol.org/specs/data-model/index.html#namespace)-specific [store](https://willowprotocol.org/specs/data-model/index.html#store).
4///
5/// A [subspace_id](https://willowprotocol.org/specs/data-model/index.html#entry_subspace_id) and a [path](https://willowprotocol.org/specs/data-model/index.html#entry_path) together uniquely identify an entry in a namespace, because between any two non-equal entries with of equal [subspace_id](https://willowprotocol.org/specs/data-model/index.html#entry_subspace_id), [path](https://willowprotocol.org/specs/data-model/index.html#entry_path), and [namespace_id](https://willowprotocol.org/specs/data-model/index.html#entry_namespace_id), one would overwrite the other.
6pub trait Keylike<const MCL: usize, const MCC: usize, const MPL: usize, S> {
7    /// Returns the [subspace_id](https://willowprotocol.org/specs/data-model/index.html#entry_subspace_id) of `self`.
8    fn wdm_subspace_id(&self) -> &S;
9
10    /// Returns the [path](https://willowprotocol.org/specs/data-model/index.html#entry_path) of `self`.
11    fn wdm_path(&self) -> &Path<MCL, MCC, MPL>;
12}
13
14impl<const MCL: usize, const MCC: usize, const MPL: usize, S> Keylike<MCL, MCC, MPL, S>
15    for (S, Path<MCL, MCC, MPL>)
16{
17    fn wdm_subspace_id(&self) -> &S {
18        &self.0
19    }
20
21    fn wdm_path(&self) -> &Path<MCL, MCC, MPL> {
22        &self.1
23    }
24}
25
26/// Methods for working with [`Keylikes`](Keylike).
27///
28/// This trait is automatically implemented by all types implementing [`Keylike`].
29pub trait KeylikeExt<const MCL: usize, const MCC: usize, const MPL: usize, S>:
30    Keylike<MCL, MCC, MPL, S>
31{
32    /// Returns whether `self` and `other` describe equal keys, i.e., whether their [subspace ids](Keylike::wdm_subspace_id) and [paths](Keylike::wdm_path) are both equal.
33    ///
34    /// # Examples
35    ///
36    /// ```
37    /// use willow_data_model::prelude::*;
38    ///
39    /// assert!(("alfie", Path::<4, 4, 4>::new()).wdm_key_eq(&("alfie", Path::<4, 4, 4>::new())));
40    /// assert!(!("alfie", Path::<4, 4, 4>::new()).wdm_key_eq(&("betty", Path::<4, 4, 4>::new())));
41    /// ```
42    fn wdm_key_eq<OtherKey>(&self, other: &OtherKey) -> bool
43    where
44        OtherKey: Keylike<MCL, MCC, MPL, S>,
45        S: PartialEq,
46    {
47        self.wdm_subspace_id() == other.wdm_subspace_id() && self.wdm_path() == other.wdm_path()
48    }
49
50    /// Returns whether `self` and `other` describe non-equal keys, i.e., whether their [subspace ids](Keylike::wdm_subspace_id) and [paths](Keylike::wdm_path) are not both equal.
51    ///
52    /// # Examples
53    ///
54    /// ```
55    /// use willow_data_model::prelude::*;
56    ///
57    /// assert!(!("alfie", Path::<4, 4, 4>::new()).wdm_key_ne(&("alfie", Path::<4, 4, 4>::new())));
58    /// assert!(("alfie", Path::<4, 4, 4>::new()).wdm_key_ne(&("betty", Path::<4, 4, 4>::new())));
59    /// ```
60    fn wdm_key_ne<OtherKey>(&self, other: &OtherKey) -> bool
61    where
62        OtherKey: Keylike<MCL, MCC, MPL, S>,
63        S: PartialEq,
64    {
65        self.wdm_subspace_id() != other.wdm_subspace_id() || self.wdm_path() != other.wdm_path()
66    }
67}
68
69impl<const MCL: usize, const MCC: usize, const MPL: usize, S, T> KeylikeExt<MCL, MCC, MPL, S> for T where
70    T: Keylike<MCL, MCC, MPL, S> + ?Sized
71{
72}
willow_data_model/groupings/keylike.rs

willow_data_model/groupings/
keylike.rs
