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=== tests/cases/compiler/wideningWithTopLevelTypeParameter.ts ===
type C1<T> = T extends unknown ? T | undefined : never;
>C1 : C1<T>
type C2<T> = T extends unknown ? T | undefined : never;
>C2 : C2<T>
type C3<T> = T extends unknown ? T | undefined : never;
>C3 : C3<T>
type C4<T> = T extends unknown ? T | undefined : never;
>C4 : C4<T>
declare function f0<T>(x: T): [T];
>f0 : <T>(x: T) => [T]
>x : T
declare function f1<T>(x: C1<T>): [T];
>f1 : <T>(x: C1<T>) => [T]
>x : C1<T>
declare function f2<T>(x: C1<C2<T>>): [T];
>f2 : <T>(x: C1<C2<T>>) => [T]
>x : C1<C2<T>>
declare function f3<T>(x: C1<C2<C3<T>>>): [T];
>f3 : <T>(x: C1<C2<C3<T>>>) => [T]
>x : C1<C2<C3<T>>>
declare function f4<T>(x: C1<C2<C3<C4<T>>>>): [T];
>f4 : <T>(x: C1<C2<C3<C4<T>>>>) => [T]
>x : C1<C2<C3<C4<T>>>>
const c0 = f0(7); // [number]
>c0 : [number]
>f0(7) : [number]
>f0 : <T>(x: T) => [T]
>7 : 7
const c1 = f1(7); // [number]
>c1 : [number]
>f1(7) : [number]
>f1 : <T>(x: C1<T>) => [T]
>7 : 7
const c2 = f2(7); // [number]
>c2 : [number]
>f2(7) : [number]
>f2 : <T>(x: C1<C2<T>>) => [T]
>7 : 7
const c3 = f3(7); // [number]
>c3 : [number]
>f3(7) : [number]
>f3 : <T>(x: C1<C2<C3<T>>>) => [T]
>7 : 7
const c4 = f4(7); // [7] since we have an internal nesting limit of 3
>c4 : [7]
>f4(7) : [7]
>f4 : <T>(x: C1<C2<C3<C4<T>>>>) => [T]
>7 : 7
// Repro from #52620
class FormControl<T> {
>FormControl : FormControl<T>
constructor(t: T extends undefined ? never : T) {}
>t : T extends undefined ? never : T
}
const a = new FormControl(''); // string
>a : FormControl<string>
>new FormControl('') : FormControl<string>
>FormControl : typeof FormControl
>'' : ""
class FormControl2<T> {
>FormControl2 : FormControl2<T>
constructor(t: T | string) {}
>t : string | T
}
const b = new FormControl2(''); // string
>b : FormControl2<string>
>new FormControl2('') : FormControl2<string>
>FormControl2 : typeof FormControl2
>'' : ""
class FormControl3<T> {
>FormControl3 : FormControl3<T>
constructor(t: T extends undefined ? never : T | string) {}
>t : T extends undefined ? never : string | T
}
const c = new FormControl3(''); // string
>c : FormControl3<string>
>new FormControl3('') : FormControl3<string>
>FormControl3 : typeof FormControl3
>'' : ""
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