Major refactor of attribute handling

codegen/src/lib.rs

@@ -96,6 +96,7 @@
 use quote::quote;
 use syn::parse_macro_input;
 
+mod attrs;
 mod function;
 mod module;
 mod register;
@@ -108,7 +109,10 @@ pub fn export_fn(
 ) -> proc_macro::TokenStream {
     let mut output = proc_macro2::TokenStream::from(input.clone());
 
-    let parsed_params = parse_macro_input!(args as function::ExportedFnParams);
+    let parsed_params = match crate::attrs::outer_item_attributes(args.into(), "export_fn") {
+        Ok(args) => args,
+        Err(err) => return proc_macro::TokenStream::from(err.to_compile_error()),
+    };
     let mut function_def = parse_macro_input!(input as function::ExportedFn);
     if let Err(e) = function_def.set_params(parsed_params) {
         return e.to_compile_error().into();