getFromPublisher.swift

import Foundation

struct XKCD: Codable {
  let month: String
  let num: Int
  let link, year, news, safeTitle: String
  let transcript, alt: String
  let img: String
  let title, day: String
  
  enum CodingKeys: String, CodingKey {
    case month, num, link, year, news, transcript,
         alt, img, title, day, safeTitle = "safe_title"
  }
}

URLGetFromPublisher.swift

import Foundation

extension URL {
  func getFromPublisher<T: Codable>(property: inout Published<T>.Publisher) {
    URLSession.shared.dataTaskPublisher(for: self)
      .receive(on: DispatchQueue.main)
      .map(\.data)
      .decode(type: T.self, decoder: JSONDecoder())
      .assertNoFailure()
      .assign(to: &property)
  }
}