AI solution for TypeScript puzzle on BFE.dev
5. implement Pick<T, K>

Here's a possible implementation of MyPick<T, K>:

type MyPick<T, K extends keyof T> = {
  [P in K]: T[P]
}

Explanation:

• We use the keyof T operator to get a union type of all keys in T.
• We constrain K to be a subset of this union type using the extends keyword.
• We define a mapped type using the in keyword, where we iterate over all keys P in K.
• For each key P, we use an index type query T[P] to get the type of the corresponding property in T.
• We use this type to define a new property in the resulting type, with the same key P. The resulting value type is T[P].

Note that this implementation creates a new type by picking properties from T based on their keys in K. This means that if K is empty, the resulting type will also be empty. Additionally, if any key in K is not a valid key in T, then the resulting type will be an error.