Trait frunk::traits::ToRef

pub trait ToRef<'a> {
    type Output;

    // Required method
    fn to_ref(&'a self) -> Self::Output;
Expand description

An alternative to AsRef that does not force the reference type to be a pointer itself.

This lets us create implementations for our recursive traits that take the resulting Output reference type, without having to deal with strange, spurious overflows that sometimes occur when trying to implement a trait for &’a T (see this comment:

This functionality is also provided as an inherent method on HLists and on Coproducts. However, you may find this trait useful in generic contexts.

Required Associated Types§

type Output

Required Methods§

fn to_ref(&'a self) -> Self::Output



impl<'a> ToRef<'a> for CNil


type Output = CNil


impl<'a> ToRef<'a> for HNil


type Output = HNil


impl<'a, CH, CTail> ToRef<'a> for Coproduct<CH, CTail>
where CH: 'a, CTail: ToRef<'a>,


type Output = Coproduct<&'a CH, <CTail as ToRef<'a>>::Output>


impl<'a, H, Tail> ToRef<'a> for HCons<H, Tail>
where H: 'a, Tail: ToRef<'a>,


type Output = HCons<&'a H, <Tail as ToRef<'a>>::Output>