1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55

use std::any::Any;

use downcast_rs::DowncastSync;

/// Trait to represent any type that is `Send + Sync + 'static`.
///
/// A resource is a data slot which lives in the `World` can only be accessed
/// according to Rust's typical borrowing model (one writer xor multiple
/// readers).
#[cfg(not(feature = "debug"))]
pub trait Resource: DowncastSync + 'static {
    fn type_name(&self) -> TypeNameLit;
}

#[cfg(not(feature = "debug"))]
impl<T> Resource for T
where
    T: Any + Send + Sync,
{
    fn type_name(&self) -> TypeNameLit {
        TypeNameLit(std::any::type_name::<T>())
    }
}

/// Trait to represent any type that is `Send + Sync + 'static`.
///
/// A resource is a data slot which lives in the `World` can only be accessed
/// according to Rust's typical borrowing model (one writer xor multiple
/// readers).
#[cfg(feature = "debug")]
pub trait Resource: DowncastSync + std::fmt::Debug + 'static {
    fn type_name(&self) -> TypeNameLit;
}

#[cfg(feature = "debug")]
impl<T> Resource for T
where
    T: Any + std::fmt::Debug + Send + Sync,
{
    fn type_name(&self) -> TypeNameLit {
        TypeNameLit(std::any::type_name::<T>())
    }
}

downcast_rs::impl_downcast!(sync Resource);

use std::fmt;

pub struct TypeNameLit(&'static str);

impl fmt::Debug for TypeNameLit {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{}", self.0)
    }
}