graph_api_lib/walker/steps/
count.rs

1use crate::walker::builder::{EdgeWalkerBuilder, VertexWalkerBuilder};
2use crate::walker::{EdgeWalker, VertexWalker};
3use include_doc::function_body;
4
5impl<'graph, Mutability, Graph, Walker> VertexWalkerBuilder<'graph, Mutability, Graph, Walker>
6where
7    Graph: crate::graph::Graph,
8    Walker: VertexWalker<'graph, Graph = Graph>,
9{
10    /// # Count Step
11    ///
12    /// The `count` step fully traverses the graph and returns the number of elements emitted by the traversal.
13    ///
14    /// ## Visual Diagram
15    ///
16    /// Before count step (with elements in traversal):
17    /// ```text
18    ///   [A]* --- edge1 ---> [B]* --- edge2 ---> [C]*  
19    ///    ^                                         
20    ///    |                                         
21    ///   edge3                                       
22    ///    |                                         
23    ///   [D]*                                        
24    /// ```
25    ///
26    /// After count step (consumed all elements, returned count 4):
27    /// ```text
28    ///   [A] --- edge1 ---> [B] --- edge2 ---> [C]  
29    ///    ^                                         
30    ///    |                                         
31    ///   edge3                                       
32    ///    |                                         
33    ///   [D]                                        
34    /// ```
35    ///
36    /// ## Parameters
37    ///
38    /// None
39    ///
40    /// ## Return Value
41    ///
42    /// Returns an integer representing the total number of elements in the traversal.
43    ///
44    /// ## Example
45    ///
46    /// ```rust
47    #[doc = function_body!("examples/count.rs", example, [])]
48    /// ```
49    ///
50    /// For more examples, see the [count example](https://github.com/yourusername/graph-api/blob/main/graph-api-lib/examples/count.rs).
51    ///
52    /// ## Notes
53    ///
54    /// - The `count` step consumes the entire traversal
55    /// - This is a terminal operation - no further steps can be added after `count`
56    /// - For very large graphs, be aware that this will traverse the entire graph which may be expensive
57    /// - Consider using `limit` before `count` if you only need to check up to a certain number of elements
58    pub fn count(mut self) -> usize
59    where
60        'graph: 'graph,
61    {
62        let mut count = 0;
63        let graph = self.graph();
64        let mut walker = self.walker();
65        while let Some(_vertex_id) = walker.next(graph) {
66            count += 1;
67        }
68        count
69    }
70}
71
72impl<'graph, Mutability, Graph, Walker> EdgeWalkerBuilder<'graph, Mutability, Graph, Walker>
73where
74    Graph: crate::graph::Graph,
75    Walker: EdgeWalker<'graph, Graph = Graph>,
76{
77    /// Counts the total number of edges in this traversal.
78    ///
79    /// This is a terminal operation that consumes the traversal.
80    ///
81    /// See the documentation for [`VertexWalkerBuilder::count`] for more details.
82    pub fn count(mut self) -> usize
83    where
84        'graph: 'graph,
85    {
86        let mut count = 0;
87        let graph = self.graph();
88        let mut walker = self.walker();
89        while let Some(_vertex_id) = walker.next(graph) {
90            count += 1;
91        }
92        count
93    }
94}
graph_api_lib/walker/steps/count.rs

graph_api_lib/walker/steps/
count.rs
