diff --git a/d3/d3.d.ts b/d3/d3.d.ts
old mode 100644
new mode 100755
index 7cb854a85d..598cd9f34b
--- a/d3/d3.d.ts
+++ b/d3/d3.d.ts
@@ -1620,6 +1620,7 @@ declare module D3 {
         export interface Symbol {
             type: (string:string) => Symbol;
             size: (number:number) => Symbol;
+            (datum:any, index:number): string;
         }
 
         export interface Brush {