abi_stable/erased_types/
type_info.rs

1//! Contains TypeInfo,metadata for a type.
2
3use std::fmt;
4
5use crate::{
6    marker_type::NonOwningPhantom,
7    sabi_types::{Constructor, MaybeCmp},
8    std_types::{utypeid::UTypeId, RStr},
9    type_level::downcasting::GetUTID,
10    InterfaceType,
11};
12
13/// Metadata about a type.
14#[derive(Debug, Eq, PartialEq)]
15#[repr(C)]
16#[derive(StableAbi)]
17pub struct TypeInfo {
18    ///
19    pub size: usize,
20    ///
21    pub alignment: usize,
22    #[doc(hidden)]
23    pub _uid: Constructor<MaybeCmp<UTypeId>>,
24    ///
25    pub type_name: Constructor<RStr<'static>>,
26    #[doc(hidden)]
27    pub _private_field: (),
28}
29
30impl TypeInfo {
31    /// Whether the `self` is the TypeInfo for the same type as `other`
32    pub fn is_compatible(&self, other: &Self) -> bool {
33        self._uid == other._uid
34    }
35}
36
37impl fmt::Display for TypeInfo {
38    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
39        writeln!(
40            f,
41            "type:{ty}\n\
42             size:{size} alignment:{alignment}\n\
43             ",
44            ty = self.type_name,
45            size = self.size,
46            alignment = self.alignment,
47        )
48    }
49}
50
51////////////////////////////////////////////
52
53#[doc(hidden)]
54pub struct TypeInfoFor<T, Interface, Downcasting>(NonOwningPhantom<(T, Interface, Downcasting)>);
55
56impl<T, Interface, Downcasting> TypeInfoFor<T, Interface, Downcasting>
57where
58    Interface: InterfaceType,
59    Downcasting: GetUTID<T>,
60{
61    /// The `&'static TypeInfo` constant, used when unerasing `DynTrait`s into a type.
62    pub const INFO: &'static TypeInfo = &TypeInfo {
63        size: std::mem::size_of::<T>(),
64        alignment: std::mem::align_of::<T>(),
65        _uid: Constructor(<Downcasting as GetUTID<T>>::UID),
66        type_name: Constructor(crate::utils::get_type_name::<T>),
67        _private_field: (),
68    };
69}
abi_stable/erased_types/type_info.rs

abi_stable/erased_types/
type_info.rs
