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=== tests/cases/conformance/types/typeRelationships/instanceOf/narrowingConstrainedTypeVariable.ts ===
// Repro from #20138
class C { }
>C : C
function f1<T extends C>(v: T | string): void {
>f1 : <T extends C>(v: T | string) => void
>v : string | T
if (v instanceof C) {
>v instanceof C : boolean
>v : string | T
>C : typeof C
const x: T = v;
>x : T
>v : T
}
else {
const s: string = v;
>s : string
>v : string
}
}
class D { }
>D : D
function f2<T extends C, U extends D>(v: T | U) {
>f2 : <T extends C, U extends D>(v: T | U) => void
>v : T | U
if (v instanceof C) {
>v instanceof C : boolean
>v : T | U
>C : typeof C
const x: T = v;
>x : T
>v : T
}
else {
const y: U = v;
>y : U
>v : U
}
}
class E { x: string | undefined }
>E : E
>x : string | undefined
function f3<T extends E>(v: T | { x: string }) {
>f3 : <T extends E>(v: T | { x: string;}) => void
>v : T | { x: string; }
>x : string
if (v instanceof E) {
>v instanceof E : boolean
>v : T | { x: string; }
>E : typeof E
const x: T = v;
>x : T
>v : T
}
else {
const y: { x: string } = v;
>y : { x: string; }
>x : string
>v : { x: string; }
}
}
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