queryItems.swift

func queryItems(dict:[String:String]) -> [URLQueryItem] {
        var items = [URLQueryItem]()
        for (name, value) in dict {
            items.append(URLQueryItem(name: name, value: value))
        }
        return items
    }

extension URLQueryItem: ExpressibleByDictionaryLiteral {
    public typealias Key = String
    public typealias Value = String
    public init(dictionaryLiteral elements: (String, String)...) {
        guard elements.count == 1
            else { fatalError("URLQueryItem requires single key-value pair") }
        self.init(name: elements.last!.0, value: elements.last!.1)
    }
}

let uq: URLQueryItem = ["key": "value"]

// and

let uqs: [URLQueryItem] = [["key1": "value1"], ["key2": "value2"], ["key3": "value3"]]

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