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=== tests/cases/conformance/types/mapped/mappedTypeConstraints2.ts ===
type Mapped1<K extends string> = { [P in K]: { a: P } };
>Mapped1 : Mapped1<K>
>a : P
function f1<K extends string>(obj: Mapped1<K>, key: K) {
>f1 : <K extends string>(obj: Mapped1<K>, key: K) => void
>obj : Mapped1<K>
>key : K
const x: { a: K } = obj[key];
>x : { a: K; }
>a : K
>obj[key] : Mapped1<K>[K]
>obj : Mapped1<K>
>key : K
}
type Mapped2<K extends string> = { [P in K as `get${P}`]: { a: P } };
>Mapped2 : Mapped2<K>
>a : P
function f2<K extends string>(obj: Mapped2<K>, key: `get${K}`) {
>f2 : <K extends string>(obj: Mapped2<K>, key: `get${K}`) => void
>obj : Mapped2<K>
>key : `get${K}`
const x: { a: K } = obj[key]; // Error
>x : { a: K; }
>a : K
>obj[key] : Mapped2<K>[`get${K}`]
>obj : Mapped2<K>
>key : `get${K}`
}
type Mapped3<K extends string> = { [P in K as Uppercase<P>]: { a: P } };
>Mapped3 : Mapped3<K>
>a : P
function f3<K extends string>(obj: Mapped3<K>, key: Uppercase<K>) {
>f3 : <K extends string>(obj: Mapped3<K>, key: Uppercase<K>) => void
>obj : Mapped3<K>
>key : Uppercase<K>
const x: { a: K } = obj[key]; // Error
>x : { a: K; }
>a : K
>obj[key] : Mapped3<K>[Uppercase<K>]
>obj : Mapped3<K>
>key : Uppercase<K>
}
// Repro from #47794
type Foo<T extends string> = {
>Foo : Foo<T>
[RemappedT in T as `get${RemappedT}`]: RemappedT;
};
const get = <T extends string>(t: T, foo: Foo<T>): T => foo[`get${t}`]; // Type 'Foo<T>[`get${T}`]' is not assignable to type 'T'
>get : <T extends string>(t: T, foo: Foo<T>) => T
><T extends string>(t: T, foo: Foo<T>): T => foo[`get${t}`] : <T extends string>(t: T, foo: Foo<T>) => T
>t : T
>foo : Foo<T>
>foo[`get${t}`] : Foo<T>[`get${T}`]
>foo : Foo<T>
>`get${t}` : `get${T}`
>t : T
// Repro from #48626
interface Bounds {
min: number;
>min : number
max: number;
>max : number
}
type NumericBoundsOf<T> = {
>NumericBoundsOf : NumericBoundsOf<T>
[K in keyof T as T[K] extends number | undefined ? K : never]: Bounds;
}
function validate<T extends object>(obj: T, bounds: NumericBoundsOf<T>) {
>validate : <T extends object>(obj: T, bounds: NumericBoundsOf<T>) => boolean
>obj : T
>bounds : NumericBoundsOf<T>
for (const [key, val] of Object.entries(obj)) {
>key : string
>val : any
>Object.entries(obj) : [string, any][]
>Object.entries : { <T>(o: { [s: string]: T; } | ArrayLike<T>): [string, T][]; (o: {}): [string, any][]; }
>Object : ObjectConstructor
>entries : { <T>(o: { [s: string]: T; } | ArrayLike<T>): [string, T][]; (o: {}): [string, any][]; }
>obj : T
const boundsForKey = bounds[key as keyof NumericBoundsOf<T>];
>boundsForKey : NumericBoundsOf<T>[keyof NumericBoundsOf<T>]
>bounds[key as keyof NumericBoundsOf<T>] : NumericBoundsOf<T>[keyof NumericBoundsOf<T>]
>bounds : NumericBoundsOf<T>
>key as keyof NumericBoundsOf<T> : keyof NumericBoundsOf<T>
>key : string
if (boundsForKey) {
>boundsForKey : NumericBoundsOf<T>[keyof NumericBoundsOf<T>]
const { min, max } = boundsForKey;
>min : number
>max : number
>boundsForKey : NumericBoundsOf<T>[keyof NumericBoundsOf<T>]
if (min > val || max < val) return false;
>min > val || max < val : boolean
>min > val : boolean
>min : number
>val : any
>max < val : boolean
>max : number
>val : any
>false : false
}
}
return true;
>true : true
}
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