Method forEach

src/typings/main/ambient/d3/d3.d.ts:1202–1202

* Calls the function for each key and value pair in the map. The 'this' context is the map itself.

(func: (key: string, value: T) => any)

         * Calls the function for each key and value pair in the map. The 'this' context is the map itself.
         */
        forEach(func: (key: string, value: T) => any): void;

        /**
         * Is this map empty?