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从其他两个泛型创建泛型

typescript

0

ThomasReggi · 技术社区 · 7 年前

DeepMerge Confine ConfineDeepMerge .

type DeepPartial<T> = {
  [P in keyof T]?: T[P] extends (infer U)[]
    ? DeepPartial<U>[]
    : T[P] extends ReadonlyArray<infer U>
      ? ReadonlyArray<DeepPartial<U>>
      : DeepPartial<T[P]>
};

type ConfineExtention<A, B> = { [K in keyof B]: K extends keyof A ? (DeepPartial<A>[K]) : never };
type Confine<A, B extends ConfineExtention<A, B>> = B;

type DeepMerge<T, U> = [T, U] extends [object, object] ?
  {
    [K in keyof (U & Pick<T, Exclude<keyof T, keyof U>>)]: (
      K extends keyof U ? (
        K extends keyof T ? DeepMerge<T[K], U[K]> : U[K]
      ) : (
        K extends keyof T ? T[K] : never
      )
    )
  } : U;

type ConfineDeepMerge<A, B> = Confine<A, DeepMerge<A, B>>;

类型“DeepMerge”不满足约束“局限扩展>”。类型“B{[K in keyof(B&Pick>)]:K extends keyof B?K extends keyof A DeepMerge:B[K]:K extends keyof A[K]:never;}不可分配给类型“CONSTRIENTEXTENTION>”。

如何合并这两个泛型?

2 回复 | 直到 7 年前

1

jcalz 7 年前

我想知道你想要什么。。。谁知道呢,也许是这样:

type ConfineMerge<T, C extends {
  [K in keyof C]: K extends keyof T ? (Partial<T>[K]) : never
}> = Pick<T, Exclude<keyof T, keyof C>> & C;

如果你能编辑这个问题来解释你想做什么,那会很有帮助。

2

0

ThomasReggi 7 年前

这是可行的,但非常冗长:

type Merge<M, N> = Omit<M, Extract<keyof M, keyof N>> & N;
// type Confine<A, B extends { [K in keyof B]: K extends keyof A ? A[K] : never }> = B;
type ConfineMerge<T, C extends ExtentionForConfineMerge<T, C>> = Pick<T, Exclude<keyof T, keyof C>> & C;
type ExtentionForConfineMerge<T, C> = {[K in keyof C]: K extends keyof T ? (Partial<T>[K]) : never};

export interface Discover <
Raw,
RawOverrides extends ExtentionForConfineMerge<Raw, RawOverrides>,
Proto extends ExtentionForConfineMerge<Merge<Raw, RawOverrides>, Proto>,
ProtoOverrides extends ExtentionForConfineMerge<Merge<Merge<Raw, RawOverrides>, Proto>, ProtoOverrides>,
> {
  Raw: Raw;
  RawOverrides: ConfineMerge<Raw, RawOverrides>;
  Proto: ConfineMerge<Merge<Raw, RawOverrides>, Proto>;
  ProtoOverrides: ConfineMerge<Merge<Merge<Raw, RawOverrides>, Proto>, ProtoOverrides>;
}