Linked list validation

gistfile1.txt

class Node {
  constructor(id, prev, isValid) {
    this.id = id
    this.prev = prev
    this.isValid = isValid
  }
  disabled() {
    return this.isValid && (this.prev ? this.prev.disabled() : true)
  }
}

const list = Array(6).fill(0).reduce((acc, n, i) => {
  const prev = i === 0 ? null : acc[i - 1]
  acc.push(new Node(i, prev, true))
  return acc
}, [])

//console.log(list[5]);
console.log(list[5].disabled());
console.log('\n\n')

list[2].isValid = false
console.log(list[2])
console.log('\n\n')
console.log(list[5].disabled());