L0v3ch4n

外观

ExtractToObject

约 215 字小于 1 分钟

2026-02-11

题目

Implement a type that extract prop value to the interface. The type takes the two arguments. The output should be an object with the prop values. Prop value is object.

For example

type Test = { id: '1', myProp: { foo: '2' }}
type Result = ExtractToObject<Test, 'myProp'> // expected to be { id: '1', foo: '2' }

解题思路

待补充

答案

type ExtractToObject<T, U> = any

验证

import type { Equal, Expect } from '@type-challenges/utils'

type test1 = { id: '1', myProp: { foo: '2' } }

type testExpect1 = {
  id: '1'
  foo: '2'
}

type test2 = {
  id: '1'
  prop1: { zoo: '2' }
  prop2: { foo: '4' }
}

type testExpect2 = {
  id: '1'
  prop1: { zoo: '2' }
  foo: '4'
}

type test3 = {
  prop1: { zoo: '2', a: 2, b: 4, c: 7 }
  prop2: { foo: '4', v: 2, d: 4, g: 7 }
  k: 289
}

type testExpect3 = {
  zoo: '2'
  a: 2
  b: 4
  c: 7
  prop2: { foo: '4', v: 2, d: 4, g: 7 }
  k: 289
}

type test4 = { id: '1', myProp: { foo: '2' } }

type testExpect4 = {
  id: '1'
  myProp: { foo: '2' }
}

type cases = [
  Expect<Equal<ExtractToObject<test1, 'myProp'>, testExpect1>>,
  Expect<Equal<ExtractToObject<test2, 'prop2'>, testExpect2>>,
  Expect<Equal<ExtractToObject<test3, 'prop1'>, testExpect3>>,
  // @ts-expect-error
  Expect<Equal<ExtractToObject<test4, 'prop4'>, testExpect4>>,
]

参考

无