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use std::any::Any;
use crate::ComputeCommand;
/// A trait that allows for cloning a trait object.
pub trait DynCloneCompute {
/// Creates a boxed clone of the trait object.
fn clone_box(&self) -> Box<dyn ComputeCommand>;
}
impl<T> DynCloneCompute for T
where
T: ComputeCommand + Clone + 'static,
{
fn clone_box(&self) -> Box<dyn ComputeCommand> {
Box::new(self.clone())
}
}
/// A trait that allows for dynamic equality testing of trait objects.
///
/// This trait provides a workaround for the fact that `PartialEq` is not object-safe.
/// It allows types that are `PartialEq` to be compared even when they are behind
/// a trait object by downcasting them to their concrete types.
pub trait DynPartialEqCompute: DynCloneCompute {
/// Returns the object as a `&dyn Any`.
fn as_any(&self) -> &dyn Any;
/// Performs a dynamic equality check against another `DynPartialEqCompute` trait object.
fn dyn_eq(&self, other: &dyn DynPartialEqCompute) -> bool;
}
impl<T: ComputeCommand + PartialEq + 'static> DynPartialEqCompute for T {
fn as_any(&self) -> &dyn Any {
self
}
fn dyn_eq(&self, other: &dyn DynPartialEqCompute) -> bool {
// Attempt to downcast the `other` trait object to the same concrete type as `self`.
if let Some(other_concrete) = other.as_any().downcast_ref::<T>() {
// If the downcast is successful, perform the actual comparison.
self == other_concrete
} else {
// If the types are different, they cannot be equal.
false
}
}
}