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//// [tests/cases/conformance/controlFlow/controlFlowInOperator.ts] ////
=== controlFlowInOperator.ts ===
const a = 'a';
>a : "a"
>'a' : "a"
const b = 'b';
>b : "b"
>'b' : "b"
const d = 'd';
>d : "d"
>'d' : "d"
type A = { [a]: number; };
>A : { a: number; }
>[a] : number
>a : "a"
type B = { [b]: string; };
>B : { b: string; }
>[b] : string
>b : "b"
declare const c: A | B;
>c : A | B
if ('a' in c) {
>'a' in c : boolean
>'a' : "a"
>c : A | B
c; // A
>c : A
c['a']; // number;
>c['a'] : number
>c : A
>'a' : "a"
}
if ('d' in c) {
>'d' in c : boolean
>'d' : "d"
>c : A | B
c; // never
>c : (A | B) & Record<"d", unknown>
}
if (a in c) {
>a in c : boolean
>a : "a"
>c : A | B
c; // A
>c : A
c[a]; // number;
>c[a] : number
>c : A
>a : "a"
}
if (d in c) {
>d in c : boolean
>d : "d"
>c : A | B
c; // never
>c : (A | B) & Record<"d", unknown>
}
// repro from https://github.com/microsoft/TypeScript/issues/54790
function uniqueID_54790(
>uniqueID_54790 : (id: string | undefined, seenIDs: { [key: string]: string; }) => string
id: string | undefined,
>id : string
seenIDs: { [key: string]: string }
>seenIDs : { [key: string]: string; }
>key : string
): string {
if (id === undefined) {
>id === undefined : boolean
>id : string
>undefined : undefined
id = "1";
>id = "1" : "1"
>id : string
>"1" : "1"
}
if (!(id in seenIDs)) {
>!(id in seenIDs) : boolean
>(id in seenIDs) : boolean
>id in seenIDs : boolean
>id : string
>seenIDs : { [key: string]: string; }
return id;
>id : string
}
for (let i = 1; i < Number.MAX_VALUE; i++) {
>i : number
>1 : 1
>i < Number.MAX_VALUE : boolean
>i : number
>Number.MAX_VALUE : number
>Number : NumberConstructor
>MAX_VALUE : number
>i++ : number
>i : number
const newID = `${id}-${i}`;
>newID : string
>`${id}-${i}` : string
>id : string
>i : number
if (!(newID in seenIDs)) {
>!(newID in seenIDs) : boolean
>(newID in seenIDs) : boolean
>newID in seenIDs : boolean
>newID : string
>seenIDs : { [key: string]: string; }
return newID;
>newID : string
}
}
throw Error("heat death of the universe");
>Error("heat death of the universe") : Error
>Error : ErrorConstructor
>"heat death of the universe" : "heat death of the universe"
}
function uniqueID_54790_2(id: string | number, seenIDs: object) {
>uniqueID_54790_2 : (id: string | number, seenIDs: object) => void
>id : string | number
>seenIDs : object
id = "a";
>id = "a" : "a"
>id : string | number
>"a" : "a"
for (let i = 1; i < 3; i++) {
>i : number
>1 : 1
>i < 3 : boolean
>i : number
>3 : 3
>i++ : number
>i : number
const newID = `${id}`;
>newID : string
>`${id}` : string
>id : string
if (newID in seenIDs) {
>newID in seenIDs : boolean
>newID : string
>seenIDs : object
}
}
}
function uniqueID_54790_3(id: string | number, seenIDs: object) {
>uniqueID_54790_3 : (id: string | number, seenIDs: object) => void
>id : string | number
>seenIDs : object
id = "a";
>id = "a" : "a"
>id : string | number
>"a" : "a"
for (let i = 1; i < 3; i++) {
>i : number
>1 : 1
>i < 3 : boolean
>i : number
>3 : 3
>i++ : number
>i : number
const newID = id;
>newID : string
>id : string
if (newID in seenIDs) {
>newID in seenIDs : boolean
>newID : string
>seenIDs : object
}
}
}
|
