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Rea Rahhal
Rea Rahhal
Courses Plus Student 4,732 Points

I am using swift 4and getting the following errors although my code is the same : extraneous argument label 'contentsOf

/AND Cannot convert return expression of type '[(String, String)]' to return type '[(String)]'

import Foundation extension String{ func addingPercentEncoding() ->String{

    return self.addingPercentEncoding(withAllowedCharacters: CharacterSet.urlQueryAllowed)!

} func encodeParametersInUrl(_ parameters:[String:Any])->String{

var components = [(String,String)]()
let sortedKeys = parameters.keys.sorted(by:{ $0 < $1 })

for key in sortedKeys{
    let value = parameters[key]
    let queryComponents = queryComponentsWith( key: key, value: value)
    components.append(contentsOf: queryComponents)

let encodedComponents = components.map{"\($0)=\($1)"}/
return encodedComponents.joined(separator: "&")


func queryComponentsWith(key:String, value:Any) -> [(String: String)]{ var components = (String,String) if let dictionary = value as? [String: Any]{ for(nestedKey,value) in dictionary{

        let nestedComponents = queryComponentsWith(key: "\(key)[\(nestedKey)]", value: value)//outer key
        components.append(contentsOf: nestedComponents)
}else if let array = value as? [Any]{
    for value in array{
        let nestedComponents = queryComponentsWith(key: "\(key)[]", value: value)
        components.append(contentsOf: nestedComponents)
    let encodedKey = key.addingPercentEncoding()
    let encodedValue = "\(value)".addingPercentEncoding()

    let component = (encodedKey,encodedValue)
return components

} let parameters = ["foo" : true] encodeParametersInUrl(parameters)