arena_system/
handle.rs

1use crate::Arena;
2use crate::Index;
3use crate::ArenaResult;
4
5use std::fmt;
6use std::cmp;
7
8use vec_cell::{ElementRef, ElementRefMut};
9
10pub trait Handle<'arena>
11where
12    Self: 'arena,
13{
14    type Type;
15    type Userdata: Clone;
16
17    fn from_raw(raw: RawHandle<'arena, Self::Type>, userdata: Self::Userdata) -> Self;
18    fn to_raw(&self) -> RawHandle<'arena, Self::Type>;
19
20    fn get(&self) -> ArenaResult<ElementRef<'arena, Self::Type>> {
21        self.to_raw().get()
22    }
23
24    fn get_mut(&self) -> ArenaResult<ElementRefMut<'arena, Self::Type>> {
25        self.to_raw().get_mut()
26    }
27
28    fn exists(&self) -> bool {
29        self.to_raw().get().is_ok()
30    }
31
32    fn arena(&self) -> &'arena Arena<Self::Type> {
33        self.to_raw().arena()
34    }
35
36    fn index(&self) -> Index {
37        self.to_raw().index()
38    }
39}
40
41pub struct RawHandle<'arena, T> {
42    arena: &'arena Arena<T>,
43    index: Index,
44}
45
46impl<'arena, T> RawHandle<'arena, T> {
47    pub(crate) fn new(arena: &'arena Arena<T>, index: Index) -> Self {
48        Self { arena, index }
49    }
50}
51
52impl<'arena, T> Handle<'arena> for RawHandle<'arena, T> {
53    type Type = T;
54    type Userdata = ();
55
56    fn from_raw(raw: RawHandle<'arena, Self::Type>, _userdata: Self::Userdata) -> Self {
57        raw
58    }
59
60    fn to_raw(&self) -> RawHandle<'arena, Self::Type> {
61        *self
62    }
63
64    fn get(&self) -> ArenaResult<ElementRef<'arena, Self::Type>> {
65        self.arena().lookup(self.index())
66    }
67
68    fn get_mut(&self) -> ArenaResult<ElementRefMut<'arena, Self::Type>> {
69        self.arena().lookup_mut(self.index())
70    }
71
72    fn arena(&self) -> &'arena Arena<Self::Type> {
73        self.arena
74    }
75
76    fn index(&self) -> Index {
77        self.index
78    }
79}
80
81impl<T> fmt::Debug for RawHandle<'_, T> {
82    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
83        f.write_fmt(format_args!("Handle({})", <Index as Into<i64>>::into(self.index)))
84    }
85}
86
87impl<T> Clone for RawHandle<'_, T> {
88    fn clone(&self) -> Self {
89        Self::new(self.arena(), self.index())
90    }
91}
92
93impl<T> Copy for RawHandle<'_, T> {}
94
95impl<T> cmp::PartialEq for RawHandle<'_, T> {
96    fn eq(&self, other: &Self) -> bool {
97        self.index() == other.index()
98    }
99}
100
101impl<T> cmp::Eq for RawHandle<'_, T> {}
102
103impl<T> cmp::PartialOrd for RawHandle<'_, T> {
104    fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
105        self.index.partial_cmp(&other.index)
106    }
107}
108
109impl<T> cmp::Ord for RawHandle<'_, T> {
110    fn cmp(&self, other: &Self) -> cmp::Ordering {
111        self.index.cmp(&other.index)
112    }
113}
arena_system/handle.rs

arena_system/
handle.rs
