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=== tests/cases/conformance/controlFlow/controlFlowForInStatement2.ts ===
const keywordA = 'a';
>keywordA : "a"
>'a' : "a"
const keywordB = 'b';
>keywordB : "b"
>'b' : "b"
type A = { [keywordA]: number };
>A : { a: number; }
>[keywordA] : number
>keywordA : "a"
type B = { [keywordB]: string };
>B : { b: string; }
>[keywordB] : string
>keywordB : "b"
declare const c: A | B;
>c : A | B
if ('a' in c) {
>'a' in c : boolean
>'a' : "a"
>c : A | B
c; // narrowed to `A`
>c : A
}
if (keywordA in c) {
>keywordA in c : boolean
>keywordA : "a"
>c : A | B
c; // also narrowed to `A`
>c : A
}
let stringB: string = 'b';
>stringB : string
>'b' : "b"
if ((stringB as 'b') in c) {
>(stringB as 'b') in c : boolean
>(stringB as 'b') : "b"
>stringB as 'b' : "b"
>stringB : string
>c : A | B
c; // narrowed to `B`
>c : B
}
if ((stringB as ('a' | 'b')) in c) {
>(stringB as ('a' | 'b')) in c : boolean
>(stringB as ('a' | 'b')) : "a" | "b"
>stringB as ('a' | 'b') : "a" | "b"
>stringB : string
>c : A | B
c; // not narrowed
>c : A | B
}
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