import Vapor
import VaporMySQL
let mysql = try VaporMySQL.Provider(host: "localhost", user: "username", password: "secret", database: "coffeeLedger")
和有什么区别
let drop = Droplet(preparations: [CoffeeLedger.self], providers: [VaporMySQL.Provider.self])
和....
let drop = Droplet(preparations: [CoffeeLedger.self], providers: [mysql])
我收到一个Cannot convert value of type 'Provider' to expected element type 'Provider.Type'
错误