networkingPlayground.swift

import Foundation
// async swift playground
import PlaygroundSupport

// https://min-api.cryptocompare.com/data/all/coinlist


let allCoinsPath = "/data/all/coinlist"

class CryptoApi {
    static let host = "min-api.cryptocompare.com"
    static let allCoinsPath = "/data/all/coinlist"
    var allCoinsUrl: URL? = {
        var urlComponents = URLComponents()
        urlComponents.scheme = "https"
        urlComponents.host = CryptoApi.host
        urlComponents.path = CryptoApi.allCoinsPath
        return urlComponents.url
    }()
}


let cryptoApi = CryptoApi()
if let allCoinsUrl = cryptoApi.allCoinsUrl {
    print(allCoinsUrl.absoluteString)
}

PlaygroundPage.current.needsIndefiniteExecution = true

reviewURLStuff.swift

// brushing up on url components
// 

class CryptoApi {
    static let host = "min-api.cryptocompare.com"
    static let allCoinsPath = "/data/all/coinlist"
    var allCoinsUrl: URL? = {
        var urlComponents = URLComponents()
        urlComponents.scheme = "https"
        urlComponents.host = CryptoApi.host
        urlComponents.path = CryptoApi.allCoinsPath
        return urlComponents.url
    }()
}