Fix type (#34)

JeromeDeLeon · bluebill1049 · commit 934c790ba113 · 2019-12-14T12:09:15.000+11:00
#30
diff --git a/src/types.ts b/src/types.ts
@@ -2,7 +2,7 @@ import * as React from 'react';
 
 export type ValidateResult = string | boolean | undefined;
 
-export type Validate = (data: any) => ValidateResult;
+export type Validate = (data: any) => ValidateResult | Promise<ValidateResult>;
 
 export type ValidationOptionObject<Value> =
   | Value
