TypeScript умеет вытаскивать типы через indexed access — помогает не дублировать типы и не объявлять всё заново.

interface UserAPIResponse {
  user: {
    id: number;
    name: string;
    email: string;
    roles: Array<{
      name: string;
      permissions: string[];
      scope: {
        resource: string;
        actions: string[];
      };
    }>;
    metadata: {
      createdAt: string;
      lastLogin: string;
    };
  };
}

// Extract types without redefining
type User = UserAPIResponse["user"];

// Extract Nested Object
type UserMetadata = UserAPIResponse["user"]["metadata"];

// Extract Array Element Type
type Role = UserAPIResponse["user"]["roles"][number];

// Extract from Nested Array
type Permission = Role["permissions"][number];
// OR (direct access)
type Permission2 = UserAPIResponse["user"]["roles"][number]["permissions"][number];

// Extract Nested Object from Nested Array
type RoleScope = UserAPIResponse["user"]["roles"][number]["scope"];
// OR (via Role type)
type RoleScope2 = Role["scope"];

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