insertionSort fun

// different attempts at insertionSort

const insert = (sortedItems, itemToInsert) => {
  if (!sortedItems.length) return sortedItems.concat(itemToInsert);
  for (const [ i, sortedItem ] of sortedItems.entries()) {
    if (itemToInsert <= sortedItem) {
      return sortedItems.slice(0, i).concat(itemToInsert).concat(...sortedItems.slice(i));
    }
  }
  return sortedItems.concat(itemToInsert);
}

const insertionSort = items => items.reduce((sortedItems, item) => insert(sortedItems, item) , []);

const sort = nums =>
  !nums.length
    ? []
    : insert(nums[0], sort(nums.slice(1)))

const insert = (numToInsert, sortedNums) =>
  !sortedNums.length
    ? [ numToInsert ]
    : (numToInsert <= sortedNums[0])
      ? [ numToInsert, ...sortedNums ]
      : [ sortedNums[0], ...insert(numToInsert, sortedNums.slice(1)) ]

const getSortedNums = nums => nums.reduce((sortedNums, num) => insert(num, sortedNums), [])

const nums = [ 6, 23, 5, 100, 7 ];

console.log(insertionSort(nums));
console.log(sort(nums));
console.log(getSortedNums(nums));