API naive example

gistfile1.swift

class API {
    private var firstCompletionHandlers: [() -> ()] = []
    private var hasCompletedFirst = false
    
    private func completeFirst() {
        hasCompletedFirst = true
        
        // API CALL RESPONSE
        if firstCompletionHandlers.count > 0 {
            for value in firstCompletionHandlers {
                value()
            }
            firstCompletionHandlers = []
        }
    }
    
    private func checkFirst(completion: () -> ()) {
        if hasCompletedFirst {
            completion()
        }
        else {
            firstCompletionHandlers.append(completion)
            first()
        }
    }
    
    func first() {
        completeFirst()
    }
    
    func second() {
        checkFirst {
            println("Second API Call")
        }
    }
}