diff --git a/codegen/src/function.rs b/codegen/src/function.rs
index a8862d20..337eccab 100644
--- a/codegen/src/function.rs
+++ b/codegen/src/function.rs
@@ -111,7 +111,7 @@ pub(crate) struct ExportedFn {
     signature: syn::Signature,
     is_public: bool,
     mut_receiver: bool,
-    pub params: ExportedFnParams,
+    params: ExportedFnParams,
 }
 
 impl Parse for ExportedFn {
@@ -218,6 +218,14 @@ impl Parse for ExportedFn {
 }
 
 impl ExportedFn {
+    pub(crate) fn params(&self) -> &ExportedFnParams {
+        &self.params
+    }
+
+    pub(crate) fn skipped(&self) -> bool {
+        self.params.skip
+    }
+
     pub(crate) fn mutable_receiver(&self) -> bool {
         self.mut_receiver
     }
diff --git a/codegen/src/module.rs b/codegen/src/module.rs
index 535ea9d7..b1a76f29 100644
--- a/codegen/src/module.rs
+++ b/codegen/src/module.rs
@@ -112,9 +112,9 @@ impl Parse for Module {
                         true
                     };
                     syn::parse2::<ExportedFn>(itemfn.to_token_stream())
-                        .map(|mut f| {
-                            f.params = params;
-                            f
+                        .and_then(|mut f| {
+                            f.set_params(params)?;
+                            Ok(f)
                         })
                         .map(|f| vec.push(f))
                         .map(|_| vec)
@@ -411,7 +411,7 @@ mod module_tests {
         assert!(item_mod.consts.is_empty());
         assert_eq!(item_mod.submodules.len(), 1);
         assert_eq!(item_mod.submodules[0].fns.len(), 1);
-        assert!(item_mod.submodules[0].fns[0].params.skip);
+        assert!(item_mod.submodules[0].fns[0].skipped());
         assert!(item_mod.submodules[0].consts.is_empty());
         assert!(item_mod.submodules[0].submodules.is_empty());
     }
@@ -433,7 +433,7 @@ mod module_tests {
         assert!(item_mod.fns.is_empty());
         assert!(item_mod.consts.is_empty());
         assert_eq!(item_mod.submodules.len(), 1);
-        assert!(item_mod.submodules[0].params.skip);
+        assert!(item_mod.submodules[0].skipped());
     }
 
     #[test]
@@ -466,7 +466,7 @@ mod module_tests {
 
         let item_mod = syn::parse2::<Module>(input_tokens).unwrap();
         assert_eq!(item_mod.fns.len(), 1);
-        assert!(item_mod.fns[0].params.skip);
+        assert!(item_mod.fns[0].skipped());
         assert!(item_mod.consts.is_empty());
     }
 
@@ -483,7 +483,7 @@ mod module_tests {
 
         let item_mod = syn::parse2::<Module>(input_tokens).unwrap();
         assert_eq!(item_mod.fns.len(), 1);
-        assert!(item_mod.fns[0].params.skip);
+        assert!(item_mod.fns[0].skipped());
         assert!(item_mod.consts.is_empty());
     }
 
diff --git a/codegen/src/rhai_module.rs b/codegen/src/rhai_module.rs
index 95f17ffc..7e1aa106 100644
--- a/codegen/src/rhai_module.rs
+++ b/codegen/src/rhai_module.rs
@@ -56,7 +56,7 @@ pub(crate) fn generate_body(
     // NB: these are token streams, because reparsing messes up "> >" vs ">>"
     let mut gen_fn_tokens: Vec<proc_macro2::TokenStream> = Vec::new();
     for function in fns {
-        if function.params.skip {
+        if function.skipped() {
             continue;
         }
         let fn_token_name = syn::Ident::new(
@@ -64,7 +64,7 @@ pub(crate) fn generate_body(
             function.name().span(),
         );
         let reg_name = function
-            .params
+            .params()
             .name
             .clone()
             .unwrap_or_else(|| function.name().to_string());
@@ -151,8 +151,8 @@ pub(crate) fn check_rename_collisions(fns: &Vec<ExportedFn>) -> Result<(), syn::
     let mut renames = HashMap::<String, proc_macro2::Span>::new();
     let mut names = HashMap::<String, proc_macro2::Span>::new();
     for itemfn in fns.iter() {
-        if let Some(ref name) = itemfn.params.name {
-            let current_span = itemfn.params.span.as_ref().unwrap();
+        if let Some(ref name) = itemfn.params().name {
+            let current_span = itemfn.params().span.as_ref().unwrap();
             let key = itemfn.arg_list().fold(name.clone(), |mut argstr, fnarg| {
                 let type_string: String = match fnarg {
                     syn::FnArg::Receiver(_) => unimplemented!("receiver rhai_fns not implemented"),