Fix the TypeScript definition for array re-use (#11)

Author: blakeembrey

array-flatten.d.ts

@@ -1,14 +1,16 @@
 declare function flatten <T> (array: flatten.NestedArray<T>): T[];
 
 declare namespace flatten {
-  interface NestedArray <T> {
-    [index: number]: T | NestedArray<T>;
+  export interface NestedArray <T> extends Array<T | NestedArray<T>> {}
+
+  export interface NestedList <T> {
+    [index: number]: T | NestedList<T>;
     length: number;
   }
 
-  export function from <T> (array: NestedArray<T>): T[];
+  export function from <T> (array: NestedList<T>): T[];
   export function depth <T> (array: NestedArray<T>, depth: number): NestedArray<T>;
-  export function depthFrom <T> (array: NestedArray<T>, depth: number): NestedArray<T>;
+  export function depthFrom <T> (array: NestedList<T>, depth: number): NestedArray<T>;
 }
 
 export = flatten;