Unconditionally derive ToComputedValue as Clone for non-generics

We assume that types such as `<Self as ToComputedValue>::ToComputedValue == Self`
just construct a new value that is just a clone of the original one without any
additional code.
This commit is contained in:
Anthony Ramine 2018-03-03 15:07:17 +01:00
parent 0eb8b1f4c0
commit b517bcd42b
2 changed files with 27 additions and 1 deletions

View file

@ -13,6 +13,29 @@ pub fn derive(input: DeriveInput) -> Tokens {
let (impl_generics, ty_generics, mut where_clause, computed_value_type) =
cg::fmap_trait_parts(&input, &trait_path, Ident::from("ComputedValue"));
if input.generics.params.is_empty() {
return quote! {
impl #impl_generics ::values::computed::ToComputedValue for #name #ty_generics
#where_clause
{
type ComputedValue = #computed_value_type;
#[inline]
fn to_computed_value(
&self,
_context: &::values::computed::Context,
) -> Self::ComputedValue {
::std::clone::Clone::clone(self)
}
#[inline]
fn from_computed_value(computed: &Self::ComputedValue) -> Self {
::std::clone::Clone::clone(computed)
}
}
}
}
let to_body = cg::fmap_match(&input, BindStyle::Ref, |binding| {
let attrs = cg::parse_field_attrs::<ComputedValueAttrs>(&binding.ast());
if attrs.clone {