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=== tests/cases/compiler/narrowingTypeofDiscriminant.ts ===
function f1(obj: { kind: 'a', data: string } | { kind: 1, data: number }) {
>f1 : Symbol(f1, Decl(narrowingTypeofDiscriminant.ts, 0, 0))
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 0, 12))
>kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 0, 18))
>data : Symbol(data, Decl(narrowingTypeofDiscriminant.ts, 0, 29))
>kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 0, 48))
>data : Symbol(data, Decl(narrowingTypeofDiscriminant.ts, 0, 57))
if (typeof obj.kind === "string") {
>obj.kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 0, 18), Decl(narrowingTypeofDiscriminant.ts, 0, 48))
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 0, 12))
>kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 0, 18), Decl(narrowingTypeofDiscriminant.ts, 0, 48))
obj; // { kind: 'a', data: string }
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 0, 12))
}
else {
obj; // { kind: 1, data: number }
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 0, 12))
}
}
function f2(obj: { kind: 'a', data: string } | { kind: 1, data: number } | undefined) {
>f2 : Symbol(f2, Decl(narrowingTypeofDiscriminant.ts, 7, 1))
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 9, 12))
>kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 9, 18))
>data : Symbol(data, Decl(narrowingTypeofDiscriminant.ts, 9, 29))
>kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 9, 48))
>data : Symbol(data, Decl(narrowingTypeofDiscriminant.ts, 9, 57))
if (typeof obj?.kind === "string") {
>obj?.kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 9, 18), Decl(narrowingTypeofDiscriminant.ts, 9, 48))
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 9, 12))
>kind : Symbol(kind, Decl(narrowingTypeofDiscriminant.ts, 9, 18), Decl(narrowingTypeofDiscriminant.ts, 9, 48))
obj; // { kind: 'a', data: string }
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 9, 12))
}
else {
obj; // { kind: 1, data: number } | undefined
>obj : Symbol(obj, Decl(narrowingTypeofDiscriminant.ts, 9, 12))
}
}
// Repro from #51700
type WrappedStringOr<T> = { value?: string } | { value?: T };
>WrappedStringOr : Symbol(WrappedStringOr, Decl(narrowingTypeofDiscriminant.ts, 16, 1))
>T : Symbol(T, Decl(narrowingTypeofDiscriminant.ts, 20, 21))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 48))
>T : Symbol(T, Decl(narrowingTypeofDiscriminant.ts, 20, 21))
function numberOk(wrapped: WrappedStringOr<number> | null) {
>numberOk : Symbol(numberOk, Decl(narrowingTypeofDiscriminant.ts, 20, 61))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 22, 18))
>WrappedStringOr : Symbol(WrappedStringOr, Decl(narrowingTypeofDiscriminant.ts, 16, 1))
if (typeof wrapped?.value !== 'string') {
>wrapped?.value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 22, 18))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
return null;
}
return wrapped.value;
>wrapped.value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 22, 18))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
}
function booleanBad(wrapped: WrappedStringOr<boolean> | null) {
>booleanBad : Symbol(booleanBad, Decl(narrowingTypeofDiscriminant.ts, 27, 1))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 29, 20))
>WrappedStringOr : Symbol(WrappedStringOr, Decl(narrowingTypeofDiscriminant.ts, 16, 1))
if (typeof wrapped?.value !== 'string') {
>wrapped?.value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 29, 20))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
return null;
}
return wrapped.value;
>wrapped.value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 29, 20))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27))
}
function booleanFixed(wrapped: WrappedStringOr<boolean> | null) {
>booleanFixed : Symbol(booleanFixed, Decl(narrowingTypeofDiscriminant.ts, 34, 1))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 36, 22))
>WrappedStringOr : Symbol(WrappedStringOr, Decl(narrowingTypeofDiscriminant.ts, 16, 1))
if (typeof (wrapped?.value) !== 'string') {
>wrapped?.value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 36, 22))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27), Decl(narrowingTypeofDiscriminant.ts, 20, 48))
return null;
}
return wrapped.value;
>wrapped.value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27))
>wrapped : Symbol(wrapped, Decl(narrowingTypeofDiscriminant.ts, 36, 22))
>value : Symbol(value, Decl(narrowingTypeofDiscriminant.ts, 20, 27))
}
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