将隐式执行上下文传递给包含的对象/调用的方法

I'm creating an async library using Scala 2.10 futures. The constructor for the library takes a sequence of user-defined objects that implement a certain trait, and then a method on the library class sends some data one-by-one into the user-defined objects. I want the user to provide the I'm creating an async library using Scala 2.10