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#![feature(const_generics)]
use core::mem::{align_of, size_of};
#[doc(hidden)]
pub struct Size<const SIZE: usize>;
#[doc(hidden)]
pub struct Align<const ALIGN: usize>;
#[doc(hidden)]
pub unsafe trait CL {
type Size;
type Align;
}
#[doc(hidden)]
unsafe impl<T> CL for T {
type Size = Size<{ size_of::<T>() }>;
type Align = Align<{ align_of::<T>() }>;
}
pub unsafe trait EqSize<Rhs> {}
#[doc(hidden)]
unsafe impl<X, Y, const S: usize> EqSize<Y> for X
where
X: CL<Size = Size<S>>,
Y: CL<Size = Size<S>>,
{
}
pub unsafe trait EqAlign<Rhs> {}
#[doc(hidden)]
unsafe impl<X, Y, const A: usize> EqAlign<Y> for X
where
X: CL<Align = Align<A>>,
Y: CL<Align = Align<A>>,
{
}
pub unsafe trait EqLayout<Rhs>: EqSize<Rhs> + EqAlign<Rhs> {}
#[doc(hidden)]
unsafe impl<X, Y> EqLayout<Y> for X where X: EqSize<Y> + EqAlign<Y> {}
#[cfg(test)]
mod tests {
use super::EqSize;
fn same_size<X: EqSize<Y>, Y>(_x: X, _y: Y) {}
#[test]
fn it_works() {
same_size(1u16, 1i16);
}
}