Generic Extends trait for pointer chains

ext/vma/src/pool.rs

@@ -39,7 +39,7 @@ pub struct PoolOptions<'a> {
 impl<'a> PoolOptions<'a> {
     pub fn push_next<T>(mut self, next: &'a mut impl vk::Cast<Target = T>) -> Self
     where
-        T: vk::ExtendsMemoryAllocateInfo,
+        T: vk::Extends<vk::MemoryAllocateInfo>,
     {
         self.next = vk::merge(self.next, NonNull::from(next).cast());
         self

generator/src/main/kotlin/com/kylemayes/generator/generate/file/Builders.kt

@@ -73,6 +73,9 @@ pub trait HasBuilder<'b> {
     }
 }
 
+/// A Vulkan struct that can be used to extend `T`
+pub unsafe trait Extends<T: InputChainStruct> {}
+
 /// Adds a base pointer chain with a new non-empty pointer chain.
 #[doc(hidden)]
 pub fn merge(base: *mut c_void, next: NonNull<BaseOutStructure>) -> *mut c_void {
@@ -175,9 +178,7 @@ private fun Registry.generateExtends(struct: Structure): String {
     }
 
     return """
-/// A Vulkan struct that can be used to extend a [`${struct.name}`].
-pub unsafe trait Extends${struct.name}: fmt::Debug { }
-${extends.joinToString("\n") { "unsafe impl Extends${struct.name} for $it { }" }}
+${extends.joinToString("\n") { "unsafe impl Extends<${struct.name}> for $it { }" }}
     """
 }
 
@@ -296,7 +297,7 @@ private fun Registry.generateNextMethod(struct: Structure): String {
 #[inline]
 pub fn push_next<T>(mut self, next: &'b mut impl Cast<Target = T>) -> Self
 where
-    T: Extends${struct.name}
+    T: Extends<${struct.name}>
 {
     self.next = merge(self.next as *mut c_void, NonNull::from(next).cast());
     self

generator/src/main/kotlin/com/kylemayes/generator/registry/Index.kt

@@ -49,15 +49,11 @@ fun Registry.indexEntities(): String {
     val versionCommands = mutableMapOf<Identifier, String>()
     val extensionCommands = mutableMapOf<Identifier, String>()
 
-    // Add builder structs and extends traits.
+    // Add builder structs.
 
     for (struct in structs.values) {
         val builder = "${struct.name}Builder"
         entities.addEntity("vk::$builder", "/vk/struct.$builder.html")
-        if (getStructExtensions().containsKey(struct.name)) {
-            val extends = "Extends${struct.name}"
-            entities.addEntity("vk::$extends", "/vk/trait.$extends.html")
-        }
     }
 
     // Add version traits.