blob: 5694d971179f275acade3cd90ce716bc3877d17e (
plain)
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
|
//! Originally from Intertrait by CodeChain
//!
//! <https://github.com/CodeChain-io/intertrait>
//! <https://crates.io/crates/intertrait/0.2.2>
//!
//! Licensed under either of
//!
//! Apache License, Version 2.0 (LICENSE-APACHE or <http://www.apache.org/licenses/LICENSE-2.0>)
//! MIT license (LICENSE-MIT or <http://opensource.org/licenses/MIT>)
//!
//! at your option.
use std::any::type_name;
use crate::libs::intertrait::cast::error::CastError;
use crate::libs::intertrait::{get_caster, CastFrom};
pub trait CastBox
{
/// Casts a box to this trait into that of type `OtherTrait`.
fn cast<OtherTrait: ?Sized + 'static>(
self: Box<Self>,
) -> Result<Box<OtherTrait>, CastError>;
}
/// A blanket implementation of `CastBox` for traits extending `CastFrom`.
impl<CastFromSelf: ?Sized + CastFrom> CastBox for CastFromSelf
{
fn cast<OtherTrait: ?Sized + 'static>(
self: Box<Self>,
) -> Result<Box<OtherTrait>, CastError>
{
let caster =
get_caster::<OtherTrait>((*self).type_id()).ok_or(CastError::CastFailed {
from: type_name::<CastFromSelf>(),
to: type_name::<OtherTrait>(),
})?;
Ok((caster.cast_box)(self.box_any()))
}
}
|
