Pick properties from a TypeScript type by their value

pick-by-value.ts

interface Dog {
  name: string;
  bark(): void;
}

declare global {
  namespace Pick {
    type ByValue<T, U> = Pick<T, PropertyOfValue<T, U>>
  }
}

type PropertyOfValue<T, V> = {
  [K in keyof T]-?: T[K] extends V
    ? K
    : never
}[keyof T];

type Methods = Pick.ByValue<Dog, Function> // { bark(): void }