+signup +login

frontend/pshared/lib/models/describable.dart

@@ -0,0 +1,39 @@
+import 'package:flutter/foundation.dart';
+
+
+abstract class Describable {
+  String get name;
+  String? get description;
+}
+
+@immutable
+class _DescribableImp implements Describable {
+  @override
+  final String name;
+  @override
+  final String? description;
+
+  const _DescribableImp({
+    required this.name,
+    required this.description,
+  });
+}
+
+Describable newDescribable({required String name, String? description}) => 
+  _DescribableImp(name: name, description: description);
+
+
+extension DescribableCopier on Describable {
+  Describable copyWith({
+    String? name,
+    String? Function()? description,
+  }) => newDescribable(
+    name: name ?? this.name,
+    description: description != null ? description() : this.description,
+  );
+}
+
+Describable describableCopyWithOther(Describable current, Describable? other) => current.copyWith(
+  name: other?.name,
+  description: () => other?.description,
+);