// WITH_STDLIB

/*
 * KOTLIN CODEGEN BOX SPEC TEST (POSITIVE)
 *
 * SPEC VERSION: 0.1-313
 * MAIN LINK: expressions, postfix-operator-expressions, postfix-increment-expression -> paragraph 6 -> sentence 1
 * PRIMARY LINKS: expressions, postfix-operator-expressions, postfix-increment-expression -> paragraph 5 -> sentence 1
 * overloadable-operators -> paragraph 4 -> sentence 1
 * statements, assignments -> paragraph 3 -> sentence 1
 * NUMBER: 1
 * DESCRIPTION:  check postfix increment expression
 */

fun box(): String {
    var a = A()
    val res: Any? = a++

    return if (res is A ) "OK"
    else "NOK"
}

class A(var i: Int = 0) {
    operator fun inc(): A {
        return A(i + 1)
    }
}