Andrew

using an implementation-dependent algorithm or strategy

If you’re like me (with a front-end background and no CS degree) you look at this and think “Ok, variable assignment, variable assignment, function… simple enough…” but then you come to s1 ^= s1 << 23; and say “what the shit?”

const data = {
  param: 'value',
  key: {
    nested: {
      double_nested: 'value'
    }
  },
  nested: {
    array: ['key 1', 'key 2']
  }
}

function getObjectKeys(obj, prefix = '') {
  const keys = Object.keys(obj).reduce((res, el) => {
    if (Array.isArray(obj[el])) {
      return [...res, ...obj[el].map((item, i) => `${prefix}${el}[${i}]`)]
    } else if (obj[el] !== null && typeof obj[el] === 'object') {
      return [...res, ...getObjectKeys(obj[el], prefix + el + '.')]
    } else {
      return [...res, prefix + el]
    }
  }, [])
  keys.sort()
  return keys
}

const array = getObjectKeys(data)
console.log(array)

.example {
    background: linear-gradient(to right, #F0F3BD, #F0F3BD), // левая граница
        linear-gradient(to right, #F0F3BD 0%, #F0F3BD 70%, #fff 70%, #fff 100%), // верхняя
        linear-gradient(to right, #F0F3BD 0%, #F0F3BD 70%, #fff 70%, #fff 100%), // нижняя
        linear-gradient(to right, #fff, #fff); // правая
    background-size: .5rem 100%, 100% .5rem, 100% .5rem, .5rem 100%;
    background-position: top left, top left, bottom left, top right;
    background-repeat: no-repeat;
}