yew_virtual/core/
virtual_key.rs

1/// Stable identity key for a virtual item.
2///
3/// Supports both numeric and string-based keys to allow custom
4/// key extractors that produce stable identities across item
5/// reordering. When items are reordered, their measured sizes
6/// follow the key rather than the index.
7#[derive(Debug, Clone, PartialEq, Eq, Hash)]
8pub enum VirtualKey {
9    /// A numeric key, typically derived from the item index.
10    Index(usize),
11
12    /// A string-based key for custom identity strategies.
13    Named(String),
14}
15
16impl Default for VirtualKey {
17    /// Returns a default key of index zero.
18    ///
19    /// # Returns
20    ///
21    /// - `VirtualKey::Index(0)`: The default key.
22    fn default() -> Self {
23        // Default to index zero.
24        Self::Index(0)
25    }
26}
27
28impl From<usize> for VirtualKey {
29    /// Creates a key from a numeric index.
30    ///
31    /// # Parameters
32    ///
33    /// - `index`: The numeric index value.
34    fn from(index: usize) -> Self {
35        // Wrap the index in the Index variant.
36        Self::Index(index)
37    }
38}
39
40impl From<String> for VirtualKey {
41    /// Creates a key from a string.
42    ///
43    /// # Parameters
44    ///
45    /// - `name`: The string key value.
46    fn from(name: String) -> Self {
47        // Wrap the string in the Named variant.
48        Self::Named(name)
49    }
50}
51
52impl From<&str> for VirtualKey {
53    /// Creates a key from a string slice.
54    ///
55    /// # Parameters
56    ///
57    /// - `name`: The string slice key value.
58    fn from(name: &str) -> Self {
59        // Convert to owned string and wrap.
60        Self::Named(name.to_string())
61    }
62}
63
64impl std::fmt::Display for VirtualKey {
65    /// Formats the key for display.
66    ///
67    /// # Parameters
68    ///
69    /// - `f`: The formatter.
70    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
71        // Delegate formatting based on variant.
72        match self {
73            Self::Index(i) => write!(f, "{}", i),
74            Self::Named(s) => write!(f, "{}", s),
75        }
76    }
77}
yew_virtual/core/virtual_key.rs

yew_virtual/core/
virtual_key.rs
