TypeScript：如何扩展这种相似的类型？

Question

如何将 IUnitedStatesAddress 扩展到 IUnitedStatesWithTerritoryAddress 而不重复自己？唯一的区别是 IUnitedStatesWithTerritoryAddress 在 state 字段中添加了 TUnitedStatesTerritoryAbbreviation。

// TypeScript Type: United States Address
export interface IUnitedStatesAddress {
  apartmentSuite: string;
  street: string;
  city: string;
  state: TUnitedStatesStateAbbreviation;
  zipCode: string;
  county: TUnitedStatesCounty;
  country: string;
}

// TypeScript Type: United States With Territory Address
export interface IUnitedStatesWithTerritoryAddress {
  apartmentSuite: string;
  street: string;
  city: string;
  state: TUnitedStatesStateAbbreviation | TUnitedStatesTerritoryAbbreviation;
  zipCode: string;
  county: TUnitedStatesCounty;
  country: string;
}

Answer 1

我很确定的一件事是你可以有一个基本接口（不导出）并用你的两个案例扩展它：

interface IUnitedStates {
  apartmentSuite: string;
  street: string;
  city: string;
  zipCode: string;
  county: TUnitedStatesCounty;
  country: string;
}

export interface IUnitedStatesAddress extends IUnitedStates {
  state: TUnitedStatesStateAbbreviation;
}

export interface IUnitedStatesWithTerritoryAddress extends IUnitedStates {
  state: TUnitedStatesStateAbbreviation | TUnitedStatesTerritoryAbbreviation;
}

TypeScript：如何扩展这种相似的类型？

TypeScript: How can I extend this type that is similar?

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