How to use can-construct - 2 common examples

// Ensure the "obj" passed as an argument has an object on @@can.meta
var ensureMeta = function ensureMeta(obj) {
	var metaSymbol = canSymbol.for("can.meta");
	var meta = obj[metaSymbol];

	if (!meta) {
		meta = {};
		canReflect.setKeyValue(obj, metaSymbol, meta);
	}

	return meta;
};

// this is a very simple can-map like object
var SimpleMap = Construct.extend("SimpleMap",
	{
		// ### setup
		// A setup function for the instantiation of a simple-map.
		setup: function(initialData){
			this._data = {};
			if(initialData && typeof initialData === "object") {
				this.attr(initialData);
			}
		},
		// ### attr
		// The main get/set interface simple-map.
		// Either sets or gets one or more properties depending on how it is called.
		attr: function(prop, value) {
			var self = this;

			if(arguments.length === 0 ) {

this.Map.prototype.setup = function(props){
				if (connection.instanceStore.has( connection.id(props) )) {
					return new Construct.ReturnValue( connection.hydrateInstance(props) );
				}
				return oldSetup.apply(this, arguments);
			};
			baseConnect.init.apply(this, arguments);