servo/components/style_derive/to_animated_zero.rs
2017-08-23 16:52:04 +02:00

32 lines
1,003 B
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use cg;
use quote;
use syn;
use synstructure::BindStyle;
pub fn derive(input: syn::DeriveInput) -> quote::Tokens {
let name = &input.ident;
let (impl_generics, ty_generics, where_clause) = cg::trait_parts(
&input,
&["values", "animated", "ToAnimatedZero"],
);
let to_body = cg::fmap_match(&input, BindStyle::Ref, |field| {
quote! { ::values::animated::ToAnimatedZero::to_animated_zero(#field)? }
});
quote! {
impl #impl_generics ::values::animated::ToAnimatedZero for #name #ty_generics #where_clause {
#[allow(unused_variables)]
#[inline]
fn to_animated_zero(&self) -> Result<Self, ()> {
Ok(match *self {
#to_body
})
}
}
}
}