TypeScriptでEnumな配列やオブジェクトから型を取得する

const names = ["Alice", "Bob", "Charlie", "David"] as const;

type Names = (typeof names)[number]; // "Alice" | "Bob" | "Charlie" | "David"

const favoriteColors = {
  alice: "cyan",
  bob: "magenta",
  charlie: "yellow",
  david: "black",
} as const;

type FavoriteColors = keyof typeof favoriteColors; // "alice" | "bob" | "charlie" | "david"

const favoriteColors = {
  alice: "cyan",
  bob: "magenta",
  charlie: "yellow",
  david: "black",
} as const;

type FavoriteColors = (typeof favoriteColors)[keyof typeof favoriteColors]; // "cyan" | "magenta" | "yellow" | "black"