Reduce.swift

typealias Handler = (Int) -> Bool

var handlers: [Handler] = []

func iterate(x: Int) {
    // commented code stops at first true
//    print(handlers.reduce(false, { $0 || $1(x) }))

    // this one iterates over all collection
    print(handlers.reduce(false, { $1(x) || $0 }))
}

handlers.append { (value) -> Bool in
    print(value)
    return value == 2
}
handlers.append { (value) -> Bool in
    print(value)
    return value == 3
}
handlers.append { (value) -> Bool in
    print(value)
    return value == 4
}

iterate(x: 2)
iterate(x: 3)
iterate(x: 4)