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=== tests/cases/compiler/typePartameterConstraintInstantiatedWithDefaultWhenCheckingDefault.ts ===
// tricky interface
interface Settable<T, V> {
set(value: V): T;
>set : (value: V) => T
>value : V
}
// implement
class Identity<V> implements Settable<Identity<V>, V> {
>Identity : Identity<V>
readonly item: V;
>item : V
constructor(value: V) {
>value : V
this.item = value;
>this.item = value : V
>this.item : V
>this : this
>item : V
>value : V
}
public set(value: V): Identity<V> {
>set : (value: V) => Identity<V>
>value : V
return new Identity<V>(value);
>new Identity<V>(value) : Identity<V>
>Identity : typeof Identity
>value : V
}
}
// generic parameter default
interface Test1<V, T extends Settable<T, V> = Identity<V>> { };
let test1: Test1<number>;
>test1 : Test1<number, Identity<number>>
// not generic parameter default
interface Test2Base<V, T extends Settable<T, V>> { };
type Test2<V> = Test2Base<V, Identity<V>>;
>Test2 : Test2<V>
let test2: Test2<number>;
>test2 : Test2<number>
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