1.ts

// -----------
// Challenge 0
// -----------

// function F<T> (f: ???): Promise<T> { 
//     return new Promise(f) 
// }

// -----------
// Challenge 1
// -----------

// export function extractPropertyByPath<V, T extends Record<string, T|V>> (obj: T, path: string): V|undefined {
function extractPropertyByPath(obj, path) {
  return undefined
}

// -----------
// Tests
// -----------

const space = {
  planets: {
    saturn: { mass: 2 } ,
    earth: { mass: 1 } ,
  },
  stars: [
    { name: 'Sun' },
  ],
}

console.assert(
  extractPropertyByPath(space, "planets.saturn.mass") == 2,
  'test 1'
)
console.assert(
  extractPropertyByPath(space, "planets.earth.mass") == 1,
  'test 2'
)
console.assert(
  extractPropertyByPath(space, "planets.moon.mass") == undefined,
  'undefined handling'
)
// console.assert(
//   extractPropertyByPath(space, "planets.stars[0].name") == 'Sun',
//   'arrays'
// )


// -----------
// Challenge 2
// -----------

// function makeExtractor<V, T extends Record<string, T|V>> (path: string): T => V|undefined
function makeExtractor (path) {
    return undefined
}

// -----------
// Tests
// -----------

const cat = {
  name: 'Mittens',
  color: {
    rgb: { r: 60, g: 60, b: 60 } ,
  }
}
const bird = {
  name: 'Tweety',
  color: {
    rgb: { r: 255, g: 255, b: 128 } ,
  }
}

// const extractor = makeExtractor('color.rgb')
// console.assert(
//   extractor(cat) == cat.color.rgb,
//   'test1'
// )
// console.assert(
//   extractor(bird) == bird.color.rgb,
//   'test2'
// )