Translate 1 file to ko - Indexed Access Types.md

[bumkeyy]

45a33fe

리뷰 부탁드려요~

추가로 index를 "색인화" 말고 그냥 인덱스라고 번역했는데 어떤가요??
의견 부탁드립니다.

[github-actions]

Thanks for the PR!

This section of the codebase is owned by @bumkeyy, @yeonjuan, @guyeol, and @dvlprsh - if they write a comment saying "LGTM" then it will be merged.

[github-actions]

Translation of Indexed Access Types.md

---

title: Indexed Access Types
layout: docs
permalink: /ko/docs/handbook/2/indexed-access-types.html

oneline: "Type['a'] Use syntax to access internal elements of a type"

To find a specific property of the type Indexed access types You can use .

type Person = { age: number; name: string; alive: boolean };
type Age = Person["age"];
//   ^?

The indexed type is a type in itself, so union, keyof Or it can be used for the whole type.

type Person = { age: number; name: string; alive: boolean };
// ---cut---
type I1 = Person["age" | "name"];
//   ^?

type I2 = Person[keyof Person];
//   ^?

type AliveOrName = "alive" | "name";
type I3 = Person[AliveOrName];
//   ^?

If you try to index a property that does not exist, you get an error.

// @errors: 2339
type Person = { age: number; name: string; alive: boolean };
// ---cut---
type I1 = Person["alve"];

Another example is that any type numberto get the type of array element.
typeofWhen combined with , you can conveniently capture element types for array literals.

const MyArray = [
  { name: "Alice", age: 15 },
  { name: "Bob", age: 23 },
  { name: "Eve", age: 38 },
];

type Person = typeof MyArray[number];
//   ^?
type Age = typeof MyArray[number]["age"];
//   ^?
// Or
type Age2 = Person["age"];
//   ^?

Used for variable references when indexing constcannot be used, only type is available.

// @errors: 2538 2749
type Person = { age: number; name: string; alive: boolean };
// ---cut---
const key = "age";
type Age = Person[key];

However, you can use type aliases with similar styles of refactors.

type Person = { age: number; name: string; alive: boolean };
// ---cut---
type key = "age";
type Age = Person[key];

Generated by 🚫 dangerJS against 45a33fe

[yeonjuan]

LGTM

[github-actions]

Merging because @yeonjuan is a code-owner of all the changes - thanks!