Make a dictionary value non-optional as extension - swift

Question

The below playground outlines my issue. The extension will remove nil values from my dictionary, but leave the other values as Optional(Value). What I need is a dictionary that has no nil values and make the optional value type non-optional.
Ex: I have a dictionary of [String:Int?]. I want the jsonSantize() of that called on that dictionary to return a [String:Int].
//: Playground - noun: a place where people can play
import UIKit
import Foundation
protocol OptionalType {
associatedtype Wrapped
var asOptional : Wrapped? { get }
}
extension Optional : OptionalType {
var asOptional : Wrapped? {
return self
}
}
extension Dictionary where Value : OptionalType{
//Sanitizes the current dictionary for json serialization
//Removes nil values entirely. Makes optionals non-optional
func jsonSanitize() -> Dictionary<Key,Value> {
var newDict:[Key:Value] = [:]
for (key, value) in self {
if value.asOptional != nil {
newDict.updateValue(self[key]!, forKey: key)
}
}
return newDict
}
}
var youGood = false
var stringMan:String? = youGood ?
"WOHOO!" :
nil
var dict:[String:Any?] = [
"stuff":"THINGIES",
"things": stringMan
]
var dict2 = dict.jsonSanitize()
print(dict2)
var test = (stringMan != nil)
UPDATE: Suggestion made to use Value.Wrapped as new dictionary type
//: Playground - noun: a place where people can play
import UIKit
import Foundation
protocol OptionalType {
associatedtype Wrapped
var asOptional : Wrapped? { get }
}
extension Optional : OptionalType {
var asOptional : Wrapped? {
return self
}
}
extension Dictionary where Value : OptionalType{
//Sanitizes the current dictionary for json serialization
//Removes nil values entirely. Makes optionals non-optional
func jsonSanitize() -> Dictionary<Key,Value.Wrapped> {
var newDict:[Key:Value.Wrapped] = [:]
for (key, value) in self {
if let v = value.asOptional {
newDict.updateValue(v, forKey: key)
}
}
return newDict
}
}
var youGood = false
var stringMan:String? = youGood ?
"WOHOO!" :
nil
var dict:[String:Any?] = [
"stuff":"THINGIES",
"things": stringMan
]
var dict2:[String:Any] = dict.jsonSanitize()
print(dict2)
var test = (stringMan != nil)

Answer 1

Your method produces a dictionary of the same type [Key: Value]
with Value being some optional type. What you probably want is
to produce a dictionary of type [Key: Value.Wrapped]:
extension Dictionary where Value: OptionalType {
func jsonSanitize() -> [Key: Value.Wrapped] {
var newDict: [Key: Value.Wrapped] = [:]
for (key, value) in self {
if let v = value.asOptional {
newDict.updateValue(v, forKey: key)
}
}
return newDict
}
}
Example:
let dict: [String: Int?] = [
"foo": 1234,
"bar": nil
]
var dict2 = dict.jsonSanitize()
print(dict2) // ["foo": 1234]
Note also that of Swift 3.0.1/Xcode 8.1 beta, optionals
are bridged to NSNull instances automatically, see
SE-0140 – Warn when Optional converts to Any, and bridge Optional As Its Payload Or NSNull