class Sammy { foo() { return "hi"; } static bar() { return -1; } } module Sammy { export var x = 1; } interface JQueryStatic { sammy: Sammy; // class instance } var $: JQueryStatic; var instanceOfClassSammy: Sammy = new $.sammy(); // should be error var r1 = instanceOfClassSammy.foo(); // r1 is string var r2 = $.sammy.foo(); var r3 = $.sammy.bar(); // error var r4 = $.sammy.x; // error Sammy.bar();