Code organization for export traits

godot-core/src/builtin/array.rs

@@ -642,7 +642,7 @@ impl<T: VariantMetadata> Share for Array<T> {
 
 impl<T: VariantMetadata + TypeStringHint> TypeStringHint for Array<T> {
     fn type_string() -> String {
-        format!("{}:{}", sys::VariantType::Array as i32, T::type_string())
+        format!("{}:{}", VariantType::Array as i32, T::type_string())
     }
 }
 

godot-core/src/obj/gd.rs

@@ -655,6 +655,9 @@ pub unsafe fn raw_object_init(
     object_ptr
 }
 
+// ----------------------------------------------------------------------------------------------------------------------------------------------
+// Trait impls
+
 /// Destructor with semantics depending on memory strategy.
 ///
 /// * If this `Gd` smart pointer holds a reference-counted type, this will decrement the reference counter.
@@ -747,8 +750,7 @@ impl<T: GodotClass> Export for Gd<T> {
     }
 }
 
-// ----------------------------------------------------------------------------------------------------------------------------------------------
-// Trait impls
+// Trait impls Property, Export and TypeStringHint for Option<Gd<T>> are covered by blanket impl for Option<T>
 
 impl<T: GodotClass> FromVariant for Gd<T> {
     fn try_from_variant(variant: &Variant) -> Result<Self, VariantConversionError> {
@@ -776,6 +778,16 @@ impl<T: GodotClass> FromVariant for Gd<T> {
     }
 }
 
+impl<T: GodotClass> FromVariant for Option<Gd<T>> {
+    fn try_from_variant(variant: &Variant) -> Result<Self, VariantConversionError> {
+        if variant.is_nil() {
+            Ok(None)
+        } else {
+            Gd::try_from_variant(variant).map(Some)
+        }
+    }
+}
+
 impl<T: GodotClass> ToVariant for Gd<T> {
     fn to_variant(&self) -> Variant {
         // The conversion method `object_to_variant` DOES increment the reference-count of the object; so nothing to do here.
@@ -807,16 +819,6 @@ impl<T: GodotClass> ToVariant for Option<Gd<T>> {
     }
 }
 
-impl<T: GodotClass> FromVariant for Option<Gd<T>> {
-    fn try_from_variant(variant: &Variant) -> Result<Self, VariantConversionError> {
-        if variant.is_nil() {
-            Ok(None)
-        } else {
-            Gd::try_from_variant(variant).map(Some)
-        }
-    }
-}
-
 impl<T: GodotClass> PartialEq for Gd<T> {
     /// ⚠️ Returns whether two `Gd` pointers point to the same object.
     ///

godot-core/src/property.rs

@@ -7,6 +7,9 @@
 use crate::builtin::GodotString;
 use crate::engine::global::PropertyHint;
 
+// ----------------------------------------------------------------------------------------------------------------------------------------------
+// Trait definitions
+
 /// Trait implemented for types that can be used as `#[var]` fields. This creates a copy of the
 /// value, for some type-specific definition of "copy". For example, `Array`, `Dictionary` and `Gd` are
 /// returned via `Share::share()` instead of copying the actual data.
@@ -23,23 +26,19 @@ pub trait Export: Property {
     fn default_export_info() -> ExportInfo;
 }
 
-/// Info needed for godot to understand how to export a type to the editor.
-#[derive(Clone, Eq, PartialEq, Debug)]
-pub struct ExportInfo {
-    pub hint: PropertyHint,
-    pub hint_string: GodotString,
+/// Trait for types that can be represented as a type string for use with
+/// [`PropertyHint::PROPERTY_HINT_TYPE_STRING`].
+pub trait TypeStringHint {
+    /// Returns the representation of this type as a type string.
+    ///
+    /// See [`PropertyHint.PROPERTY_HINT_TYPE_STRING`](
+    ///     https://docs.godotengine.org/en/stable/classes/class_%40globalscope.html#enum-globalscope-propertyhint
+    /// ).
+    fn type_string() -> String;
 }
 
-impl ExportInfo {
-    /// Create a new `ExportInfo` with a property hint of
-    /// [`PROPERTY_HINT_NONE`](PropertyHint::PROPERTY_HINT_NONE).
-    pub fn with_hint_none() -> Self {
-        Self {
-            hint: PropertyHint::PROPERTY_HINT_NONE,
-            hint_string: GodotString::new(),
-        }
-    }
-}
+// ----------------------------------------------------------------------------------------------------------------------------------------------
+// Blanket impls for Option<T>
 
 impl<T: TypeStringHint> TypeStringHint for Option<T> {
     fn type_string() -> String {
@@ -80,15 +79,25 @@ where
     }
 }
 
-/// Trait for types that can be represented as a type string for use with
-/// [`PropertyHint::PROPERTY_HINT_TYPE_STRING`].
-pub trait TypeStringHint {
-    /// Returns the representation of this type as a type string.
-    ///
-    /// See [`PropertyHint.PROPERTY_HINT_TYPE_STRING`](
-    ///     https://docs.godotengine.org/en/stable/classes/class_%40globalscope.html#enum-globalscope-propertyhint
-    /// ).
-    fn type_string() -> String;
+// ----------------------------------------------------------------------------------------------------------------------------------------------
+// Export machinery
+
+/// Info needed for godot to understand how to export a type to the editor.
+#[derive(Clone, Eq, PartialEq, Debug)]
+pub struct ExportInfo {
+    pub hint: PropertyHint,
+    pub hint_string: GodotString,
+}
+
+impl ExportInfo {
+    /// Create a new `ExportInfo` with a property hint of
+    /// [`PROPERTY_HINT_NONE`](PropertyHint::PROPERTY_HINT_NONE).
+    pub fn with_hint_none() -> Self {
+        Self {
+            hint: PropertyHint::PROPERTY_HINT_NONE,
+            hint_string: GodotString::new(),
+        }
+    }
 }
 
 /// To export properties to Godot, you must have an impl-block with the `#[godot_api]` attribute, even if