facet_reflect/peek/
map.rs

1use facet_core::{MapDef, PtrConst, PtrMut};
2
3use super::Peek;
4
5/// Iterator over key-value pairs in a `PeekMap`
6pub struct PeekMapIter<'mem, 'facet_lifetime> {
7    map: PeekMap<'mem, 'facet_lifetime>,
8    iter: PtrMut<'mem>,
9}
10
11impl<'mem, 'facet_lifetime> Iterator for PeekMapIter<'mem, 'facet_lifetime> {
12    type Item = (Peek<'mem, 'facet_lifetime>, Peek<'mem, 'facet_lifetime>);
13
14    fn next(&mut self) -> Option<Self::Item> {
15        unsafe {
16            let next = (self.map.def.vtable.iter_vtable.next)(self.iter);
17            next.map(|(key_ptr, value_ptr)| {
18                (
19                    Peek::unchecked_new(key_ptr, self.map.def.k),
20                    Peek::unchecked_new(value_ptr, self.map.def.v),
21                )
22            })
23        }
24    }
25}
26
27impl Drop for PeekMapIter<'_, '_> {
28    fn drop(&mut self) {
29        unsafe { (self.map.def.vtable.iter_vtable.dealloc)(self.iter) }
30    }
31}
32
33impl<'mem, 'facet_lifetime> IntoIterator for &'mem PeekMap<'mem, 'facet_lifetime> {
34    type Item = (Peek<'mem, 'facet_lifetime>, Peek<'mem, 'facet_lifetime>);
35    type IntoIter = PeekMapIter<'mem, 'facet_lifetime>;
36
37    fn into_iter(self) -> Self::IntoIter {
38        self.iter()
39    }
40}
41
42/// Lets you read from a map (implements read-only [`facet_core::MapVTable`] proxies)
43#[derive(Clone, Copy)]
44pub struct PeekMap<'mem, 'facet_lifetime> {
45    pub(crate) value: Peek<'mem, 'facet_lifetime>,
46
47    pub(crate) def: MapDef,
48}
49
50impl core::fmt::Debug for PeekMap<'_, '_> {
51    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
52        f.debug_struct("PeekMap").finish_non_exhaustive()
53    }
54}
55
56impl<'mem, 'facet_lifetime> PeekMap<'mem, 'facet_lifetime> {
57    /// Constructor
58    pub fn new(value: Peek<'mem, 'facet_lifetime>, def: MapDef) -> Self {
59        Self { value, def }
60    }
61
62    /// Get the number of entries in the map
63    pub fn len(&self) -> usize {
64        unsafe { (self.def.vtable.len_fn)(self.value.data()) }
65    }
66
67    /// Returns true if the map is empty
68    pub fn is_empty(&self) -> bool {
69        self.len() == 0
70    }
71
72    /// Check if the map contains a key
73    pub fn contains_key(&self, key: &impl facet_core::Facet<'facet_lifetime>) -> bool {
74        unsafe {
75            let key_ptr = PtrConst::new(key);
76            (self.def.vtable.contains_key_fn)(self.value.data(), key_ptr)
77        }
78    }
79
80    /// Get a value from the map for the given key
81    pub fn get<'k>(
82        &self,
83        key: &'k impl facet_core::Facet<'facet_lifetime>,
84    ) -> Option<Peek<'mem, 'facet_lifetime>> {
85        unsafe {
86            let key_ptr = PtrConst::new(key);
87            let value_ptr = (self.def.vtable.get_value_ptr_fn)(self.value.data(), key_ptr)?;
88            Some(Peek::unchecked_new(value_ptr, self.def.v))
89        }
90    }
91
92    /// Returns an iterator over the key-value pairs in the map
93    pub fn iter(self) -> PeekMapIter<'mem, 'facet_lifetime> {
94        let iter = unsafe { (self.def.vtable.iter_fn)(self.value.data()) };
95        PeekMapIter { map: self, iter }
96    }
97
98    /// Def getter
99    pub fn def(&self) -> MapDef {
100        self.def
101    }
102}
facet_reflect/peek/map.rs

facet_reflect/peek/
map.rs
