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//// [objectTypeWithRecursiveWrappedPropertyCheckedNominally.ts]
// Types with infinitely expanding recursive types are type checked nominally
class List<T> {
data: T;
next: List<List<T>>;
}
class MyList<T> {
data: T;
next: MyList<MyList<T>>;
}
var list1 = new List<number>();
var list2 = new List<string>();
var myList1 = new MyList<number>();
var myList2 = new MyList<string>();
list1 = myList1; // error, not nominally equal
list1 = myList2; // error, type mismatch
list2 = myList1; // error, not nominally equal
list2 = myList2; // error, type mismatch
var rList1 = new List<List<number>>();
var rMyList1 = new List<MyList<number>>();
rList1 = rMyList1; // error, not nominally equal
function foo<T extends List<number>, U extends MyList<number>>(t: T, u: U) {
t = u; // error
u = t; // error
var a: List<number>;
var b: MyList<number>;
a = t; // ok
a = u; // error
b = t; // error
b = u; // ok
}
function foo2<T extends U, U extends MyList<number>>(t: T, u: U) {
t = u; // error
u = t; // was error, ok after constraint made illegal, doesn't matter
var a: List<number>;
var b: MyList<number>;
a = t; // error
a = u; // error
b = t; // ok
b = u; // ok
}
//// [objectTypeWithRecursiveWrappedPropertyCheckedNominally.js]
// Types with infinitely expanding recursive types are type checked nominally
var List = /** @class */ (function () {
function List() {
}
return List;
}());
var MyList = /** @class */ (function () {
function MyList() {
}
return MyList;
}());
var list1 = new List();
var list2 = new List();
var myList1 = new MyList();
var myList2 = new MyList();
list1 = myList1; // error, not nominally equal
list1 = myList2; // error, type mismatch
list2 = myList1; // error, not nominally equal
list2 = myList2; // error, type mismatch
var rList1 = new List();
var rMyList1 = new List();
rList1 = rMyList1; // error, not nominally equal
function foo(t, u) {
t = u; // error
u = t; // error
var a;
var b;
a = t; // ok
a = u; // error
b = t; // error
b = u; // ok
}
function foo2(t, u) {
t = u; // error
u = t; // was error, ok after constraint made illegal, doesn't matter
var a;
var b;
a = t; // error
a = u; // error
b = t; // ok
b = u; // ok
}
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