docs: add cases() documentation to README

README.md

@@ -55,6 +55,7 @@ Method
 [Enum::names(): array](#enumnames)
 [Enum::values(): array](#enumvalues)
 [Enum::entries(): array](#enumentries)
+[Enum::cases(): array](#enumcases)
 
 ## Enum::fromName()
 
@@ -166,3 +167,24 @@ enum HelloWorld: string {
 
 HelloWorld::entries(); // ["FOO" => "BAR", "BAZ" => "QUX"]
 ```
+
+## Enum::cases()
+
+Return an array of `Enum` instances for all cases in the enum.
+
+```php
+Enum::cases(): array<Enum>
+```
+
+Example:
+
+```php
+enum HelloWorld: string {
+    use xEnum;
+    
+    case FOO = "BAR";
+    case BAZ = "QUX";
+}
+
+HelloWorld::cases(); // [object<Enum::FOO>, object<Enum::BAZ>]
+```