Restructured library.

lib/interface.js

@@ -0,0 +1,30 @@
+// In order to test this interface implementation run jsc interface.js
+
+export default class Interface {
+    // Abstract interface that should be extended in interface subclasses.
+    // By convention all interfaces should start with an upper 'I'
+
+    static implementationError(klass) {
+        let interfaceKeys = Reflect.ownKeys(this.prototype)
+        let classKeys = Reflect.ownKeys(klass.prototype)
+        for(let key of interfaceKeys) {
+            let interfaceDesc = this.prototype[key]
+            let classDesc = klass.prototype[key]
+            if (typeof(classDesc) == 'undefined')
+                return 'Missing ' + key
+        }
+        return null
+    }
+
+    static implementedBy(klass) {
+        // In the first step only checks whether the methods of this
+        // interface are all implemented by the given class
+        let error = this.implementationError(klass)
+        return error == null
+    }
+
+        // TODO: Specify optional methods
+//     static optionalMethods() {
+//         return [this.onMouseWheel]
+//     }
+}