In Part 2 of this series I introduced isolate scope and how it can be used to make directives more re-useable. A big part of isolate scope is local scope properties that rely on characters such as @, = and & to handle data binding as well as function delegation. By using these properties you can pass data into and out of AngularJS directives. If you’re new to local scope properties in directives I’d recommend reading the first two posts in this series. In this post I’ll explore passing parameters out of a directive into an external function.