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#![allow(dead_code)]
#![warn(clippy::expl_impl_clone_on_copy)]
#[derive(Copy)]
struct Qux;
impl Clone for Qux {
fn clone(&self) -> Self {
Qux
}
}
// looks like unions don't support deriving Clone for now
#[derive(Copy)]
union Union {
a: u8,
}
impl Clone for Union {
fn clone(&self) -> Self {
Union { a: 42 }
}
}
// See #666
#[derive(Copy)]
struct Lt<'a> {
a: &'a u8,
}
impl<'a> Clone for Lt<'a> {
fn clone(&self) -> Self {
unimplemented!()
}
}
#[derive(Copy)]
struct BigArray {
a: [u8; 65],
}
impl Clone for BigArray {
fn clone(&self) -> Self {
unimplemented!()
}
}
#[derive(Copy)]
struct FnPtr {
a: fn() -> !,
}
impl Clone for FnPtr {
fn clone(&self) -> Self {
unimplemented!()
}
}
// Ok, Clone trait impl doesn't have constrained generics.
#[derive(Copy)]
struct Generic<T> {
a: T,
}
impl<T> Clone for Generic<T> {
fn clone(&self) -> Self {
unimplemented!()
}
}
#[derive(Copy)]
struct Generic2<T>(T);
impl<T: Clone> Clone for Generic2<T> {
fn clone(&self) -> Self {
Self(self.0.clone())
}
}
// Ok, Clone trait impl doesn't have constrained generics.
#[derive(Copy)]
struct GenericRef<'a, T, U>(T, &'a U);
impl<T: Clone, U> Clone for GenericRef<'_, T, U> {
fn clone(&self) -> Self {
Self(self.0.clone(), self.1)
}
}
fn main() {}
|
