Create identical-objects-in-dart.dart

Author: vandadnp

tipsandtricks/identical-objects-in-dart/identical-objects-in-dart.dart

@@ -0,0 +1,41 @@
+import 'dart:developer' as devtools show log;
+
+extension Log on Object {
+  void log() => devtools.log(toString());
+}
+
+void testIt() {
+  const person1 = Person(name: 'Vandad', age: 42);
+  const person2 = Person(name: 'Vandad', age: 42);
+  const person3 = Person(name: 'Vandad', age: 43);
+  identical(person1, person2).log(); // true
+  (person1 == person2).log(); // true
+  (person1 == person3).log(); // false
+  (person2 == person3).log(); // false
+  (person3 == person3).log(); // true
+}
+
+@immutable
+class Person {
+  final String name;
+  final int age;
+
+  const Person({
+    required this.name,
+    required this.age,
+  });
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is Person &&
+          runtimeType == other.runtimeType &&
+          name == other.name &&
+          age == other.age;
+
+  @override
+  int get hashCode => Object.hashAll([
+        name,
+        age,
+      ]);
+}