Let modules decide their own name via #[cdef] macro

crates/luaffi/src/lib.rs

@@ -158,16 +158,16 @@ impl Registry {
         self
     }
 
-    pub fn preload<T: Type>(&mut self, name: impl Display) -> &mut Self {
+    pub fn preload<T: Module>(&mut self) -> &mut Self {
         assert!(T::ty() != TypeType::Void, "cannot declare void type");
-        self.include::<T>();
-        let ct = T::name();
+        let name = <T as Module>::name();
+        let ct = <T as Type>::name();
         writeln!(
             self.lua,
             r#"__preload["{name}"] = function(...) return __ct.{ct}(...); end;"#,
         )
         .unwrap();
-        self
+        self.include::<T>()
     }
 
     pub fn build(&self) -> String {
@@ -240,6 +240,10 @@ impl<'r> TypeBuilder<'r> {
     }
 }
 
+pub trait Module: Type {
+    fn name() -> impl Display;
+}
+
 pub unsafe trait Cdef: Type {
     fn build(b: &mut CdefBuilder);
 }
@@ -320,6 +324,7 @@ pub struct MetatypeBuilder<'r> {
     ct: String,
     cdef: String,
     lua: String,
+    lua_includes: Vec<&'static str>,
 }
 
 impl<'r> MetatypeBuilder<'r> {
@@ -329,6 +334,7 @@ impl<'r> MetatypeBuilder<'r> {
             ct: T::Target::name().to_string(),
             cdef: String::new(),
             lua: r#"do local __mt, __idx = {}, {}; __mt.__index = __idx; "#.into(),
+            lua_includes: vec![],
         }
     }
 
@@ -337,6 +343,11 @@ impl<'r> MetatypeBuilder<'r> {
         self
     }
 
+    pub fn include_lua(&mut self, lua: &'static str) -> &mut Self {
+        self.lua_includes.push(lua);
+        self
+    }
+
     pub fn index(
         &mut self,
         name: impl Display,
@@ -377,12 +388,15 @@ impl<'r> Drop for MetatypeBuilder<'r> {
             ct,
             cdef,
             lua,
-            ..
+            lua_includes: lua_postlude,
         } = self;
 
         registry.cdef.push_str(cdef);
         registry.lua.push_str(lua);
         writeln!(registry.lua, r#"__metatype(__ct.{ct}, __mt); end;"#).unwrap();
+        for lua in lua_postlude {
+            writeln!(registry.lua, r#"do {lua} end;"#).unwrap();
+        }
     }
 }