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=== tests/cases/compiler/paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts ===
// Using a homomorphic mapped type over `T`
// Produces a lower-priority inference for `T` than other
// positions, allowing one to override the priority the argument
// order would usually imply
type Lower<T> = { [K in keyof T]: T[K] };
>Lower : Symbol(Lower, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 0, 0))
>T : Symbol(T, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 11))
>K : Symbol(K, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 19))
>T : Symbol(T, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 11))
>T : Symbol(T, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 11))
>K : Symbol(K, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 19))
export function appendToOptionalArray<
>appendToOptionalArray : Symbol(appendToOptionalArray, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 41))
K extends string | number | symbol,
>K : Symbol(K, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 6, 38))
T
>T : Symbol(T, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 7, 37))
>(
object: { [x in K]?: Lower<T>[] },
>object : Symbol(object, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 9, 2))
>x : Symbol(x, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 10, 13))
>K : Symbol(K, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 6, 38))
>Lower : Symbol(Lower, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 0, 0))
>T : Symbol(T, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 7, 37))
key: K,
>key : Symbol(key, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 10, 36))
>K : Symbol(K, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 6, 38))
value: T
>value : Symbol(value, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 11, 9))
>T : Symbol(T, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 7, 37))
) {
const array = object[key];
>array : Symbol(array, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 14, 7))
>object : Symbol(object, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 9, 2))
>key : Symbol(key, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 10, 36))
if (array) {
>array : Symbol(array, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 14, 7))
array.push(value);
>array.push : Symbol(Array.push, Decl(lib.es5.d.ts, --, --))
>array : Symbol(array, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 14, 7))
>push : Symbol(Array.push, Decl(lib.es5.d.ts, --, --))
>value : Symbol(value, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 11, 9))
} else {
object[key] = [value];
>object : Symbol(object, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 9, 2))
>key : Symbol(key, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 10, 36))
>value : Symbol(value, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 11, 9))
}
}
// e.g.
const foo: {x?: number[]; y?: string[]; } = {};
>foo : Symbol(foo, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 23, 5))
>x : Symbol(x, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 23, 12))
>y : Symbol(y, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 23, 25))
appendToOptionalArray(foo, 'x', 123); // ok
>appendToOptionalArray : Symbol(appendToOptionalArray, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 41))
>foo : Symbol(foo, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 23, 5))
appendToOptionalArray(foo, 'y', 'bar'); // ok
>appendToOptionalArray : Symbol(appendToOptionalArray, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 41))
>foo : Symbol(foo, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 23, 5))
appendToOptionalArray(foo, 'y', 12); // should fail
>appendToOptionalArray : Symbol(appendToOptionalArray, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 41))
>foo : Symbol(foo, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 23, 5))
appendToOptionalArray(foo, 'x', "no"); // should fail
>appendToOptionalArray : Symbol(appendToOptionalArray, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 4, 41))
>foo : Symbol(foo, Decl(paramsOnlyHaveLiteralTypesWhenAppropriatelyContextualized.ts, 23, 5))
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