by jiangshan @jiangshanmeta
Implement a generic PartialByKeys<T, K> which takes two type argument T and K.
K specify the set of properties of T that should set to be optional. When K is not provided, it should make all properties optional just like the normal Partial<T>.
For example
interface User {
name: string
age: number
address: string
}
type UserPartialName = PartialByKeys<User, 'name'> // { name?:string; age:number; address:string }
