Update derive parsing to produce structured representation
diff --git a/syntax/mod.rs b/syntax/mod.rs
index 3eb6c6e..9e4cbbc 100644
--- a/syntax/mod.rs
+++ b/syntax/mod.rs
@@ -46,7 +46,7 @@
 
 pub struct Struct {
     pub doc: Doc,
-    pub derives: Vec<Ident>,
+    pub derives: Vec<Derive>,
     pub struct_token: Token![struct],
     pub ident: Ident,
     pub brace_token: Brace,