generic_callback.swift

// Playground - noun: a place where people can play

import UIKit

struct ApiResponse {
    let success: Bool
    let values: [[NSObject: AnyObject]]
}

class BaseModel: NSObject {
    
    class func arrayFromApi<T: BaseModel>(response: ApiResponse, success: ([T] -> Void), failure: (NSError -> Void)) {
        if response.success {
            success(response.values.map { T(values: $0) })
        }
    }
    
    required init(values: [NSObject: AnyObject]) {
        super.init()
        setValuesForKeysWithDictionary(values)
    }
}

class SubModel: BaseModel {
    dynamic var prop1: String!
    
    override var description: String {
        return "SubModel(prop1: \(prop1))"
    }
}

let response = ApiResponse(success: true, values: [["prop1": "something"], ["prop1": "nothing"]])

SubModel.arrayFromApi(response, success: { (models: [SubModel]) in
        println(models)
    }, failure: { error in
        
})