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|
=== tests/cases/compiler/discriminantsAndNullOrUndefined.ts ===
// Repro from #10228
interface A { kind: 'A'; }
>kind : "A"
interface B { kind: 'B'; }
>kind : "B"
type C = A | B | undefined;
>C : C
function never(_: never): never {
>never : (_: never) => never
>_ : never
throw new Error();
>new Error() : Error
>Error : ErrorConstructor
}
function useA(_: A): void { }
>useA : (_: A) => void
>_ : A
function useB(_: B): void { }
>useB : (_: B) => void
>_ : B
declare var c: C;
>c : C
if (c !== undefined) {
>c !== undefined : boolean
>c : C
>undefined : undefined
switch (c.kind) {
>c.kind : "A" | "B"
>c : A | B
>kind : "A" | "B"
case 'A': useA(c); break;
>'A' : "A"
>useA(c) : void
>useA : (_: A) => void
>c : A
case 'B': useB(c); break;
>'B' : "B"
>useB(c) : void
>useB : (_: B) => void
>c : B
default: never(c);
>never(c) : never
>never : (_: never) => never
>c : never
}
}
|
