diff --git a/syntax/parse.rs b/syntax/parse.rs
index efe6ff8..1453b30 100644
--- a/syntax/parse.rs
+++ b/syntax/parse.rs
@@ -1,5 +1,5 @@
 use crate::syntax::{
-    attrs, error, Api, Atom, Doc, ExternFn, ExternType, Receiver, Ref, Struct, Ty1, Type, Var,
+    self, attrs, error, Api, Atom, Doc, ExternFn, ExternType, Receiver, Ref, Struct, Ty1, Type, Var,
 };
 use proc_macro2::Ident;
 use quote::quote;
@@ -251,6 +251,9 @@
                 }
             }
         }
+        RustType::Tuple(ty) if ty.elems.is_empty() => {
+            return Ok(Type::Void(syntax::Span(ty.paren_token.span)));
+        }
         _ => {}
     }
     Err(Error::new_spanned(ty, "unsupported type"))