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Refer: Easy - Pick
Describe
Implement the built-in Pick<T, K>
generic without using it.
Constructs a type by picking the set of properties K from T
For example
code snippetCopytypescriptinterface Todo {
title: string
description: string
completed: boolean
}
type TodoPreview = MyPick<Todo, 'title' | 'completed'>
const todo: TodoPreview = {
title: 'Clean room',
completed: false,
}
Test Cases
code snippetCopytypescriptimport { Equal, Expect } from '@type-challenges/utils'
type cases = [
Expect<Equal<Expected1, MyPick<Todo, 'title'>>>,
Expect<Equal<Expected2, MyPick<Todo, 'title' | 'completed'>>>,
// @ts-expect-error
MyPick<Todo, 'title' | 'completed' | 'invalid'>,
]
interface Todo {
title: string
description: string
completed: boolean
}
interface Expected1 {
title: string
}
interface Expected2 {
title: string
completed: boolean
}
Solution
code snippetCopytypescripttype MyPick<T, K extends keyof T> = {
[P in K]: T[P]
}