alex/nih-plug
1
0
Fork 0
Code Activity

Split finding and processing proc macro attributes

Browse source 
We're going to add another attribute that can't be combined with this
one.
This commit is contained in:
Robbert van der Helm 2022-01-28 13:00:36 +01:00
parent b91a02baa6
commit a9185dff21
1 changed files with 17 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

21
nih_plug_derive/src/lib.rs
View file

@ -33,17 +33,30 @@ pub fn derive_params(input: TokenStream) -> TokenStream {
_ => continue,
};
// We'll add another attribute for persistent fields later, and that's going to be mutually
// exclusive with this id attribute
let mut id_attr = None;
for attr in field.attrs {
let list = match attr.parse_meta() {
Ok(syn::Meta::List(list)) if list.path.is_ident("id") => list,
_ => continue,
match attr.parse_meta() {
Ok(syn::Meta::List(list)) if list.path.is_ident("id") => {
if id_attr.is_none() {
id_attr = Some(list);
} else {
return syn::Error::new(attr.span(), "Duplicate id attribute")
.to_compile_error()
.into();
}
}
_ => (),
};
}
if let Some(list) = id_attr {
let param_id =
match list.nested.first() {
Some(syn::NestedMeta::Lit(syn::Lit::Str(s))) => s.value(),
_ => return syn::Error::new(
attr.span(),
list.span(),
"The id attribute should have a single string argument: #[id(\"foo_bar\")]",
)
.to_compile_error()