Update

Author: MatheusDS4

src/SUMMARY.md

@@ -7,6 +7,8 @@
   - [Type conversion](./as3/type-conversion.md)
   - [Type matching](./as3/type-matching.md)
   - [Classes](./as3/classes.md)
+  - [Enums](./as3/enums.md)
+  - [Interfaces](./as3/interfaces.md)
   - [Namespaces](./as3/namespaces.md)
   - [Events](./as3/events.md)
   - [Environment variables](./as3/environment.md)

src/as3/enums.md

@@ -0,0 +1,17 @@
+# Enums
+
+Enums are special classes consisting of zero or more variants. Use the `enum` definition to define enums.
+
+```
+enum Variant {
+    const VARIANT_ONE;
+    const VARIANT_TWO = "variantTwo";
+    const VARIANT_THREE = [2, "variantThree"];
+}
+```
+
+## Type inference
+
+```
+var v : Variant = "variantOne";
+```

src/as3/interfaces.md

@@ -0,0 +1,18 @@
+# Interfaces
+
+Interfaces are non opaque types that may be implemented by classes through the `implements` clause.
+
+```
+interface I {
+    //
+    public function m() : void;
+
+    //
+    public function get x() : Number;
+    public function set x(value);
+}
+
+interface Ia extends I {}
+```
+
+All interface methods must omit the body.