Add combine_with_exported_module.

codegen/src/lib.rs

@@ -152,6 +152,20 @@ pub fn exported_module(module_path: proc_macro::TokenStream) -> proc_macro::Toke
     proc_macro::TokenStream::from(tokens)
 }
 
+#[proc_macro]
+pub fn combine_with_exported_module(args: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    #[allow(unused_variables)]
+    let (module_expr, export_name, module_path) = match crate::register::parse_register_macro(args)
+    {
+        Ok(triple) => triple,
+        Err(e) => return e.to_compile_error().into(),
+    };
+    let tokens = quote! {
+        #module_path::rhai_generate_into_module(#module_expr);
+    };
+    proc_macro::TokenStream::from(tokens)
+}
+
 #[proc_macro]
 pub fn register_exported_fn(args: proc_macro::TokenStream) -> proc_macro::TokenStream {
     let (engine_expr, export_name, rust_modpath) = match crate::register::parse_register_macro(args)

codegen/src/module.rs

@@ -191,6 +191,7 @@ impl Parse for Module {
     }
 }
 
+#[allow(dead_code)]
 impl Module {
     pub fn attrs(&self) -> Option<&Vec<syn::Attribute>> {
         self.mod_all.as_ref().map(|m| &m.attrs)

codegen/src/rhai_module.rs

@@ -17,6 +17,7 @@ pub(crate) fn generate_body(
     let mut set_fn_stmts: Vec<syn::Stmt> = Vec::new();
     let mut set_const_stmts: Vec<syn::Stmt> = Vec::new();
     let mut add_mod_blocks: Vec<syn::ExprBlock> = Vec::new();
+    let mut set_mod_blocks: Vec<syn::ExprBlock> = Vec::new();
     let str_type_path = syn::parse2::<syn::Path>(quote! { str }).unwrap();
 
     for (const_name, const_expr) in consts {
@@ -54,6 +55,14 @@ pub(crate) fn generate_body(
             })
             .unwrap(),
         );
+        set_mod_blocks.push(
+            syn::parse2::<syn::ExprBlock>(quote! {
+                #(#cfg_attrs)* {
+                    self::#module_name::rhai_generate_into_module(m);
+                }
+            })
+            .unwrap(),
+        );
     }
 
     // NB: these are token streams, because reparsing messes up "> >" vs ">>"
@@ -137,6 +146,11 @@ pub(crate) fn generate_body(
                 #(#add_mod_blocks)*
                 m
             }
+            pub fn rhai_generate_into_module(m: &mut Module) {
+                #(#set_fn_stmts)*
+                #(#set_const_stmts)*
+                #(#set_mod_blocks)*
+            }
         }
     })
     .unwrap();