Next item or first of array

next-recurse.ts

/**
 Will find the next/prev element from an array based on given element. Will loop back to first/last if given step value exceeds
 the bounds of the items

 @remarks

 {@link https://tinyurl.com/r3nhday | GH Gist url}

 @example
```ts
 const val1 = nextRecurse(items, 'b')
 const val2 = nextRecurse(items, 'd')
 const val3 = nextRecurse(items, 'b', 2)
 const val4 = nextRecurse(items, 'b', -2)
 const val5 = nextRecurse(items, 'b', -6)
 const val6 = nextRecurse(items, 'b', 6)
 
 console.log('val1 :', val1);
 console.log('val2 :', val2);
 console.log('val3 :', val3);
 console.log('val4 :', val4);
 console.log('val5 :', val5);
 console.log('val6 :', val6);
```
 */
const nextRecurse = <T extends any = string>(items: T[], item: T, step = 1): T => {
  const index = items.indexOf(item)
  if (index === -1) throw new Error(`Unrecognised item '${item}'`)
  let intendedIndex = index + step
  if (intendedIndex >= items.length) intendedIndex = intendedIndex % items.length
  if (intendedIndex < 0) intendedIndex = items.length + (intendedIndex % items.length)
  return items[intendedIndex]
}