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//// [tests/cases/conformance/types/typeRelationships/apparentType/apparentTypeSubtyping.ts] ////
=== apparentTypeSubtyping.ts ===
// subtype checks use the apparent type of the target type
// S is a subtype of a type T, and T is a supertype of S, if one of the following is true, where S' denotes the apparent type (section 3.8.1) of S:
class Base<U extends String> {
>Base : Base<U>
x: U;
>x : U
}
// is String (S) a subtype of U extends String (T)? Would only be true if we used the apparent type of U (T)
class Derived<U> extends Base<string> { // error
>Derived : Derived<U>
>Base : Base<string>
x: String;
>x : String
}
class Base2 {
>Base2 : Base2
x: String;
>x : String
static s: String;
>s : String
}
// is U extends String (S) a subtype of String (T)? Apparent type of U is String so it succeeds
class Derived2<U extends String> extends Base2 { // error because of the prototype's not matching, not because of the instance side
>Derived2 : Derived2<U>
>Base2 : Base2
x: U;
>x : U
}
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