type GetOptional<T> = {
  [k in keyof T as  T[k] extends Required<T>[k] ? never : k]: T[k]
}

Solution by wendao-liu #35168

type GetOptional<T> = {
  [k in keyof T as T[k] extends Required<T>[k] ? never : k]?: T[k]
}

Solution by floatDreamWithSong #34987

type IsKeyOptional<T extends Record<string, any>, K extends keyof T> = {
  [P in K]?: T[P]
} extends Pick<T, K> ? true : false

type GetOptional<T extends Record<string, any>, K extends keyof T = keyof T> = {
  [P in K as IsKeyOptional<T, P> extends true ? P : never]: T[P]
}

Solution by ktim816 #34450

type GetOptional<T> = {
  [K in keyof T as T extends Record<K, T[K]> ? never : K]: T[K]
}

Solution by skeleton1231 #34343

type GetOptional<T extends object> = {
  [K in keyof T as T[K] extends Required<T>[K] ? never : K]: T[K]
}

Solution by ouzexi #34205

// your answers
type GetOptional<T> = {
  [key in keyof T as {} extends Pick<T,key> ? key:never]:T[key]
}

Solution by sciencefunq #32916

和 这个挑战逻辑一样

type GetOptional<T, M = Required<T>> = {
  [P in keyof (T | M) as Equal<T[P], M[P]> extends true ? never : P]: T[P];
};

Solution by Vampirelee #32603

type GetOptional<T> = {[P in keyof T as T[P] extends Required<T>[P] ? never: P]: T[P]}

// here Required<T>[P] ? never :P   remove the required key and pic optional one

Solution by wubrafiq807 #32561

// your answers
type GetOptional<T> = {
  [K in keyof T as T[K] extends Required<T>[K] ? never : K]: T[K]
}

Solution by laqudee #32361

type GetOptional = { [key in keyof T as (T[key] extends {[reqKey in keyof T]-?: T[reqKey]}[key] ? never : key)] : T[key] }

Solution by harshtalks #31670

type GetOptional<T> = {
  [P in keyof T as T[P] extends Required<T>[P] ? never : P]: T[P];
};

Solution by vipulpathak113 #31320

type GetOptional<T> = {
  [K in keyof T as Pick<T, K> extends Required<Pick<T, K>> ? never : K]: T[K]
}

Solution by dreamluo-plus #30719

type Exclude<A, B> = {
  [K in keyof A & keyof B]:
    A[K] extends B[K] ? never : K
};

type OptionalKeys<T> = Exclude<T, Required<T>>[keyof T];

type GetOptional<T> = {
  [K in OptionalKeys<T>]?: T[K]
};

Solution by denysoblohin-okta #30427

type GetOptional<T> = {
  [K in keyof T as {[E in K]+?: T[E]} extends {[E in K]:T[E]} ? K : never] : T[K]
}

Solution by gyermakavets #28281

type MyRequired<T> = {
  [key in keyof T]-?: T[key]
}


type GetOptional<T> = {
  [key in keyof T as T[key] extends MyRequired<T>[key] ? never : key]: T[key]
}

Solution by wuxin0011 #27557

type GetOptional<T> = { [K in keyof T as T[K] extends Required<T>[K] ? never : K]: T[K] }

Solution by smileboyi #27332

// 你的答案
type GetOptional<T> = {
  [
    P in keyof T as
      T[P] extends Required<T>[P]
      ? never
      : P
  ]: T[P];
};

Solution by kiki-zjq #25984

// your answers
type GetOptional<T extends object> = {
  [K in keyof T as T[K] extends Required<T>[K] ? never : K]: T[K]
}

Solution by studymachiney #24956

type GetOptional<T> = { [P in keyof T as T[P] extends Required<T>[P] ? never : P]: T[P] };  //-?后类型仍相同则为必选字段

Solution by E-uler #24670

type GetOptional<T> = {
  [Key in keyof T as T[Key] extends Required<T>[Key] ? never : Key]: T[Key]
}

Solution by NeylonR #24415

type GetOptional<T extends Record<string, any>> = matchOptionalKey<T, GetKeys<T>>;

type GetKeys<T> = {
  [k in keyof T]: k;
};

type matchOptionalKey<T extends Record<string, any>, U extends Record<string, any>, k = keyof U> = k extends keyof U ? undefined extends U[k] ? {
  [m in k]?: m extends keyof T ? T[m] : never;
} : never : never;

Solution by yolilufei #24357

// 你的答案

type GetOptional<T> = {
  [K in keyof T as T[K] extends Required<T>[K]?never:K]:T[K]
}

Solution by walker-hzx #24297

type GetOptional<T> = {[Key in keyof T as  {} extends Pick<T, Key> ? Key: never]: T[Key]}

Solution by sabercc #23857

type GetOptional<T> = {
  [K in keyof T as {} extends Pick<T, K> ? K : never]: T[K]
}

Solution by snakeUni #23410

// 你的答案
type GetOptional<T> = {
  [K in keyof T as ({} extends Pick<T, K> ? K : never)]: T[K]
}

Solution by jxhhdx #22818

type GetOptional<T> = {
  [Key in keyof T as T[Key] extends Required<T>[Key] ? never : Key]: T[Key]
}

Solution by drylint #22193

type GetOptional<T extends object> = {[K in keyof T as T[K] extends Required<T>[K] ? never : K]: T[K]}

Solution by kfess #21918

type GetRequired<T> = {
  [key in keyof T as T[key] extends Required<T>[key] ? key : never] : T[key]
}

type GetOptional<T> = Omit<T, keyof GetRequired<T>>;

Solution by Karamuto #21883

// 你的答案
type GetOptional<T>
    = { [K in keyof T as T[K] extends { [K in keyof T]-?: T[K] }[K] ? never : K]: T[K] }

Solution by goddnsgit #21844

type GetOptional<T extends object> = {
  [K in keyof T as T[K] extends Required<T>[K] ? never : K]: T[K]
}

Solution by jgjgill #21822