wip

Author: Wandalen

module/core/former_meta/src/derive_former/former_enum.rs

@@ -14,10 +14,34 @@ use macro_tools::
 #[ cfg( feature = "derive_former" ) ]
 use convert_case::{ Case, Casing }; // Space before ;
 
+
 // ==================================
 //      Enum Variant Handling Rules (Consistent Logic)
 // ==================================
-// ... (Rules documentation remains the same) ...
+//
+// This macro implements the `Former` derive for enums based on the following consistent rules:
+//
+// 1.  **`#[scalar]` Attribute:**
+//     *   **Unit Variant:** Generates `Enum::variant() -> Enum`.
+//     *   **Zero-Field Variant Generates `Enum::variant() -> Enum`.
+//     *   **Single-Field Variant (Tuple or Struct):** Generates `Enum::variant(InnerType) -> Enum`.
+//     *   **Multi-Field Variant (Tuple or Struct):** Generates `Enum::variant(Field1Type, Field2Type, ...) -> Enum`.
+//     *   **Error Cases:** Cannot be combined with `#[subform_scalar]`.
+//
+// 2.  **`#[subform_scalar]` Attribute:**
+//     *   **Unit Variant:** Error.
+//     *   **Zero-Field Variant (Tuple or Struct):** Error.
+//     *   **Single-Field Variant (Tuple or Struct):** Generates `Enum::variant() -> InnerFormer<...>` (where `InnerFormer` is the former for the field's type). Requires the field type to be a path type deriving `Former`.
+//     *   **Multi-Field Variant (Tuple or Struct):** Generates `Enum::variant() -> InnerFormer<...>` (where `InnerFormer` is the former for the field's type). Requires the field type to be a path type deriving `Former`.
+//
+// 3.  **Default Behavior (No Attribute):**
+//     *   **Unit Variant:** Generates `Enum::variant() -> Enum`.
+//     *   **Zero-Field Variant Generates `Enum::variant() -> Enum`.
+//     *   **Single-Field Variant (Tuple or Struct):** Generates `Enum::variant() -> InnerFormer<...>` (where `InnerFormer` is the former for the field's type). Requires the field type to be a path type deriving `Former`.
+//     *   **Multi-Field Variant (Tuple or Struct):** Generates `Enum::variant() -> InnerFormer<...>` (where `InnerFormer` is the former for the field's type). Requires the field type to be a path type deriving `Former`.
+//
+// Body attribute `standalone_constructors` creates stand-alone, top-level constructors for struct/enum. for struct it's always single function, for enum it's as many functions as enum has vartianys.
+//
 // ==================================
 
 /// Temporary storage for field information needed during generation.