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=== tests/cases/compiler/higherOrderMappedIndexLookupInference.ts ===
// @strict
function f1(a: <T>() => keyof T, b: <U>() => keyof U) {
>f1 : (a: <T>() => keyof T, b: <U>() => keyof U) => void
>a : <T>() => keyof T
>b : <U>() => keyof U
a = b;
>a = b : <U>() => keyof U
>a : <T>() => keyof T
>b : <U>() => keyof U
b = a;
>b = a : <T>() => keyof T
>b : <U>() => keyof U
>a : <T>() => keyof T
}
function f2(a: <T, K extends keyof T>() => T[K], b: <U, L extends keyof U>() => U[L]) {
>f2 : (a: <T, K extends keyof T>() => T[K], b: <U, L extends keyof U>() => U[L]) => void
>a : <T, K extends keyof T>() => T[K]
>b : <U, L extends keyof U>() => U[L]
a = b;
>a = b : <U, L extends keyof U>() => U[L]
>a : <T, K extends keyof T>() => T[K]
>b : <U, L extends keyof U>() => U[L]
b = a;
>b = a : <T, K extends keyof T>() => T[K]
>b : <U, L extends keyof U>() => U[L]
>a : <T, K extends keyof T>() => T[K]
}
function f3(a: <T>() => { [K in keyof T]: T[K] }, b: <U>() => { [K in keyof U]: U[K] }) {
>f3 : (a: <T>() => { [K in keyof T]: T[K]; }, b: <U>() => { [K in keyof U]: U[K]; }) => void
>a : <T>() => { [K in keyof T]: T[K]; }
>b : <U>() => { [K in keyof U]: U[K]; }
a = b;
>a = b : <U>() => { [K in keyof U]: U[K]; }
>a : <T>() => { [K in keyof T]: T[K]; }
>b : <U>() => { [K in keyof U]: U[K]; }
b = a;
>b = a : <T>() => { [K in keyof T]: T[K]; }
>b : <U>() => { [K in keyof U]: U[K]; }
>a : <T>() => { [K in keyof T]: T[K]; }
}
// Repro from #18338
type IdMapped<T> = { [K in keyof T]: T[K] }
>IdMapped : IdMapped<T>
declare const f: <T>() => IdMapped<T>;
>f : <T>() => IdMapped<T>
declare const g: <U>() => { [K in keyof U]: U[K] };
>g : <U>() => { [K in keyof U]: U[K]; }
const h: typeof g = f;
>h : <U>() => { [K in keyof U]: U[K]; }
>g : <U>() => { [K in keyof U]: U[K]; }
>f : <T>() => IdMapped<T>
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