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/**
* 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 crate::libs::intertrait::{caster, CastFrom};
pub trait CastBox
{
/// Casts a box to this trait into that of type `T`. If fails, returns the receiver.
fn cast<T: ?Sized + 'static>(self: Box<Self>) -> Result<Box<T>, Box<Self>>;
}
/// A blanket implementation of `CastBox` for traits extending `CastFrom`.
impl<S: ?Sized + CastFrom> CastBox for S
{
fn cast<T: ?Sized + 'static>(self: Box<Self>) -> Result<Box<T>, Box<Self>>
{
match caster::<T>((*self).type_id()) {
Some(caster) => Ok((caster.cast_box)(self.box_any())),
None => Err(self),
}
}
}
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