Extending Array only when the element type is of a specific type

Question

I want to extend the array type only when its elements is of a specific type. In this case I'm using instances of EKCalendar.

This does not work:

public extension Array where Generator.Element : EKCalendar{

}

But this Does:

public extension CollectionType where Generator.Element : EKCalendar{

}

Why is it I can only do this with a protocol ?

Marco Boschi · Accepted Answer · 2015-09-22 20:07:57Z

3

While extending Array you cannot access Generator.Element because it's part of the CollectionType protocol, you need to use Element:

public extension Array where Element: EKCalendar {
   //....
}

answered Sep 22, 2015 at 20:07

Marco Boschi

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