xsl 0.1.1

A simple library
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140

extern crate alloc;
extern crate std;
use alloc::string::String;
use alloc::vec::Vec;
use std::collections::BTreeMap;
use std::collections::HashSet;
#[derive(Debug)]
pub struct Finder<T> {
    root: Node<T>,
    miss_count: usize,
    ignore_case: bool,
}
impl<T> Default for Finder<T> {
    fn default() -> Self {
        Self::new(3, true)
    }
}
impl<T> Extend<(String, T)> for Finder<T> {
    fn extend<I: IntoIterator<Item = (String, T)>>(&mut self, iter: I) {
        for (word, value) in iter {
            self.insert(word, value);
        }
    }
}
#[derive(Debug)]
struct Node<T> {
    children: BTreeMap<char, Node<T>>,
    values: Vec<T>,
}
impl<T> Finder<T> {
    pub fn new(miss_count: usize, ignore_case: bool) -> Self {
        Self {
            root: Node {
                children: BTreeMap::new(),
                values: Vec::new(),
            },
            miss_count,
            ignore_case,
        }
    }
    /// Insert a word and its value into the FuzzyFinder.
    pub fn insert(&mut self, mut word: String, value: T) {
        let mut node = &mut self.root;
        if self.ignore_case {
            word = word.to_lowercase();
        }
        for c in word.chars() {
            node = node.children.entry(c).or_insert(Node {
                children: BTreeMap::new(),
                values: Vec::new(),
            });
        }
        node.values.push(value);
    }
    /// Search a word in the FuzzyFinder.
    /// Return the value if the word is found, otherwise return None.
    /// # Example
    /// ```
    /// use xsl::collections::FuzzyFinder;
    /// let mut finder = FuzzyFinder::default();
    /// finder.insert("hello".to_string(), 1);
    /// assert_eq!(finder.search("hello".to_string()), Some(vec![&1]));
    /// assert_eq!(finder.search("world".to_string()), None);
    /// ```
    pub fn search(&self, mut word: String) -> Option<Vec<&T>> {
        if self.ignore_case {
            word = word.to_lowercase();
        }
        let mut node = &self.root;
        for c in word.chars() {
            if let Some(n) = node.children.get(&c) {
                node = n;
            } else {
                return None;
            }
        }
        (!node.values.is_empty()).then(|| node.values.iter().collect())
    }
    /// Search a word prefix in the FuzzyFinder.
    /// Return the values if the word prefix is found, otherwise return None.
    /// # Example
    /// ```
    /// use xsl::collections::FuzzyFinder;
    /// let mut finder = FuzzyFinder::default();
    /// finder.insert("hello".to_string(), 1);
    /// finder.insert("ello".to_string(), 2);
    /// assert_eq!(finder.search_prefix("he".to_string()), Some(vec![&1]));
    /// assert_eq!(finder.search_prefix("e".to_string()), Some(vec![&2, &1]));
    /// assert_eq!(finder.search_prefix("w".to_string()), None);
    /// ```
    pub fn search_prefix(&self, mut word: String) -> Option<Vec<&T>> {
        if self.ignore_case {
            word = word.to_lowercase();
        }
        let mut valid_nodes = Vec::new();
        let mut dedup = HashSet::new();
        let mut stack = Vec::new();
        stack.push((&self.root, word.chars(), 0));
        while let Some((cur_node, mut words, miss_count)) = stack.pop() {
            let back = words.clone();
            match words.next() {
                Some(c) => {
                    for (kw, node) in cur_node.children.iter().rev() {
                        if kw == &c {
                            stack.push((node, words.clone(), 0));
                        }
                        if miss_count < self.miss_count {
                            stack.push((node, back.clone(), miss_count + 1));
                        }
                    }
                }
                None => {
                    if dedup.insert(cur_node as *const Node<T>) {
                        valid_nodes.push(cur_node);
                    }
                }
            }
        }
        dedup.clear();
        let mut over = Vec::new();
        while let Some(n) = valid_nodes.pop() {
            if !n.values.is_empty() && dedup.insert(n as *const Node<T>) {
                over.push(n);
            }
            for node in n.children.values() {
                valid_nodes.push(node);
            }
        }
        if over.is_empty() {
            return None;
        }
        Some(
            over.iter()
                .rev()
                .map(|n| n.values.iter())
                .flatten()
                .collect(),
        )
    }
}