facet_reflect/peek/
map.rs

1use facet_core::{MapDef, PtrMut};
2
3use crate::ReflectError;
4
5use super::Peek;
6
7/// Iterator over key-value pairs in a `PeekMap`
8pub struct PeekMapIter<'mem, 'facet> {
9    map: PeekMap<'mem, 'facet>,
10    iter: PtrMut<'mem>,
11}
12
13impl<'mem, 'facet> Iterator for PeekMapIter<'mem, 'facet> {
14    type Item = (Peek<'mem, 'facet>, Peek<'mem, 'facet>);
15
16    #[inline]
17    fn next(&mut self) -> Option<Self::Item> {
18        unsafe {
19            let next = (self.map.def.vtable.iter_vtable.next)(self.iter);
20            next.map(|(key_ptr, value_ptr)| {
21                (
22                    Peek::unchecked_new(key_ptr, self.map.def.k()),
23                    Peek::unchecked_new(value_ptr, self.map.def.v()),
24                )
25            })
26        }
27    }
28}
29
30impl<'mem, 'facet> Drop for PeekMapIter<'mem, 'facet> {
31    #[inline]
32    fn drop(&mut self) {
33        unsafe { (self.map.def.vtable.iter_vtable.dealloc)(self.iter) }
34    }
35}
36
37impl<'mem, 'facet> IntoIterator for &'mem PeekMap<'mem, 'facet> {
38    type Item = (Peek<'mem, 'facet>, Peek<'mem, 'facet>);
39    type IntoIter = PeekMapIter<'mem, 'facet>;
40
41    #[inline]
42    fn into_iter(self) -> Self::IntoIter {
43        self.iter()
44    }
45}
46
47/// Lets you read from a map (implements read-only [`facet_core::MapVTable`] proxies)
48#[derive(Clone, Copy)]
49pub struct PeekMap<'mem, 'facet> {
50    pub(crate) value: Peek<'mem, 'facet>,
51
52    pub(crate) def: MapDef,
53}
54
55impl<'mem, 'facet> core::fmt::Debug for PeekMap<'mem, 'facet> {
56    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
57        f.debug_struct("PeekMap").finish_non_exhaustive()
58    }
59}
60
61impl<'mem, 'facet> PeekMap<'mem, 'facet> {
62    /// Constructor
63    #[inline]
64    pub fn new(value: Peek<'mem, 'facet>, def: MapDef) -> Self {
65        Self { value, def }
66    }
67
68    /// Get the number of entries in the map
69    #[inline]
70    pub fn len(&self) -> usize {
71        unsafe { (self.def.vtable.len_fn)(self.value.data()) }
72    }
73
74    /// Returns true if the map is empty
75    #[inline]
76    pub fn is_empty(&self) -> bool {
77        self.len() == 0
78    }
79
80    /// Check if the map contains a key
81    #[inline]
82    pub fn contains_key(&self, key: &impl facet_core::Facet<'facet>) -> Result<bool, ReflectError> {
83        self.contains_key_peek(Peek::new(key))
84    }
85
86    /// Get a value from the map for the given key
87    #[inline]
88    pub fn get<'k>(
89        &self,
90        key: &'k impl facet_core::Facet<'facet>,
91    ) -> Result<Option<Peek<'mem, 'facet>>, ReflectError> {
92        self.get_peek(Peek::new(key))
93    }
94
95    /// Check if the map contains a key
96    #[inline]
97    pub fn contains_key_peek(&self, key: Peek<'_, 'facet>) -> Result<bool, ReflectError> {
98        if self.def.k() == key.shape {
99            return Ok(unsafe { (self.def.vtable.contains_key_fn)(self.value.data(), key.data()) });
100        }
101
102        Err(ReflectError::WrongShape {
103            expected: self.def.k(),
104            actual: key.shape,
105        })
106    }
107
108    /// Get a value from the map for the given key
109    #[inline]
110    pub fn get_peek(
111        &self,
112        key: Peek<'_, 'facet>,
113    ) -> Result<Option<Peek<'mem, 'facet>>, ReflectError> {
114        if self.def.k() == key.shape {
115            return Ok(unsafe {
116                let Some(value_ptr) =
117                    (self.def.vtable.get_value_ptr_fn)(self.value.data(), key.data())
118                else {
119                    return Ok(None);
120                };
121                Some(Peek::unchecked_new(value_ptr, self.def.v()))
122            });
123        }
124
125        Err(ReflectError::WrongShape {
126            expected: self.def.k(),
127            actual: key.shape,
128        })
129    }
130
131    /// Returns an iterator over the key-value pairs in the map
132    #[inline]
133    pub fn iter(self) -> PeekMapIter<'mem, 'facet> {
134        let iter_init_with_value_fn = self.def.vtable.iter_vtable.init_with_value.unwrap();
135        let iter = unsafe { iter_init_with_value_fn(self.value.data()) };
136        PeekMapIter { map: self, iter }
137    }
138
139    /// Def getter
140    #[inline]
141    pub fn def(&self) -> MapDef {
142        self.def
143    }
144}