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=== tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembersOptionality2.ts ===
// Derived member is optional but base member is not, should be an error
interface Base { foo: string; }
>foo : string
interface Derived extends Base { bar: string; }
>bar : string
interface T {
Foo: Base;
>Foo : Base
}
interface S extends T {
Foo?: Derived // error
>Foo : Derived
}
interface T2 {
1: Base;
>1 : Base
}
interface S2 extends T2 {
1?: Derived; // error
>1 : Derived
}
interface T3 {
'1': Base;
>'1' : Base
}
interface S3 extends T3 {
'1'?: Derived; // error
>'1' : Derived
}
// object literal case
var a: { Foo: Base; }
>a : { Foo: Base; }
>Foo : Base
var b: { Foo?: Derived; }
>b : { Foo?: Derived; }
>Foo : Derived
var r = true ? a : b; // ok
>r : { Foo: Base; } | { Foo?: Derived; }
>true ? a : b : { Foo: Base; } | { Foo?: Derived; }
>true : true
>a : { Foo: Base; }
>b : { Foo?: Derived; }
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