graph_api_lib/
index.rs

1use std::any::TypeId;
2use std::fmt::{Debug, Display};
3use std::hash::Hash;
4
5/// The type of index
6#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
7#[non_exhaustive]
8pub enum IndexType {
9    /// A hash index that supports lookup by value.
10    Hash,
11    /// A range index that supports range search
12    Range,
13    /// A full text index
14    FullText,
15}
16
17impl Display for IndexType {
18    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
19        match self {
20            IndexType::Hash => write!(f, "hash"),
21            IndexType::Range => write!(f, "range"),
22            IndexType::FullText => write!(f, "full text"),
23        }
24    }
25}
26
27/// An Index is a fast lookup mechanism for graph elements.
28///
29/// Indexes allow for efficient querying of graph elements based on different criteria.
30/// Each index has a type and can be identified by an ordinal within its type.
31pub trait Index
32where
33    Self: Sized + Copy + Eq + Hash + Debug,
34{
35    /// Returns the TypeId of the element being indexed.
36    ///
37    /// Supported types are graph dependent, but all graph implementations support
38    /// basic Rust types and strings.
39    fn ty(&self) -> TypeId;
40
41    /// Returns the ordinal number of this index.
42    ///
43    /// The ordinal uniquely identifies an index within its index type.
44    fn ordinal(&self) -> usize;
45
46    /// Returns the type of this index (Hash, Range, or FullText).
47    fn index_type(&self) -> IndexType;
48}
49
50impl Index for () {
51    fn ty(&self) -> TypeId {
52        unimplemented!("index not implemented")
53    }
54
55    fn ordinal(&self) -> usize {
56        unimplemented!("index not implemented")
57    }
58
59    fn index_type(&self) -> IndexType {
60        unimplemented!("index not implemented")
61    }
62}
graph_api_lib/index.rs

graph_api_lib/
index.rs
