How is this different from List Item Shifter?

List Item Shifter drops items that shift off the front (or pads with empty items), so the list's content changes. List Rotator wraps those items around to the other end instead, so every original item is always still present, just reordered.

What happens if N is larger than the list length?

N is taken modulo the list length, so rotating a 4-item list by 6 behaves the same as rotating it by 2, since a full rotation of 4 brings the list back to where it started.

Does rotation ever lose or duplicate items?

No, rotation is a pure reordering. The same items, in the same multiset, always come back out, just starting from a different position.

What's the difference between left and right rotation?

A left rotation moves items toward the front of the list, with items from the front wrapping around to the end. A right rotation moves items toward the end, with items from the end wrapping around to the front.

List Rotator Online - True Wrap-Around List Rotation

Overview

Introduction

Rotating a list, cycling its items around so the first becomes last (or the last becomes first), comes up constantly in scheduling, round-robin assignment, and cyclic data structures.

List Rotator performs that true wrap-around rotation, so every item is preserved, just shifted to a new starting position.

What Is List Rotator?

A tool that rotates a list left or right by N positions with genuine wrap-around: items shifted off one end reappear at the other end rather than being dropped.

It's deliberately distinct from List Item Shifter, which drops or pads instead of wrapping, they solve related but different problems.

How List Rotator Works

The rotation amount N is reduced modulo the list length (so a rotation larger than the list simply wraps around one or more extra full cycles), then the list is split at the resulting position.

For a left rotation, everything from that split point onward comes first, followed by everything before it; a right rotation does the mirror-image split.

When To Use List Rotator

Use it for round-robin assignment, cycling through a list of people, servers, or tasks so a different item starts first each time.

It's also useful for simulating a circular buffer or ring structure on a plain-text list.

Often used alongside List Item Shifter, List Mirror and Sublist Extractor.

Features

Advantages

Never loses or duplicates items, rotation is always a pure, lossless reordering.
Handles rotation amounts larger than the list length correctly via modulo arithmetic, no manual reduction needed.
Works with any configured separator, not just newline-delimited lists.

Limitations

Only performs a single rotation direction and amount per run; combine multiple runs (or just add the amounts) for compound rotations.
Rotation amount must be zero or positive; use the direction toggle (left/right) rather than a negative number to rotate the other way.

Examples

Rotate left by 1

Input

1
2
3
4 (direction: left, N=1)

Output

The first item ("1") wraps around to the end; every other item shifts one position toward the front.

Rotate right by 1

Input

1,2,3,4 (direction: right, N=1)

Output

4, 1, 2, 3

The last item ("4") wraps around to the front; every other item shifts one position toward the end.

Best Practices & Notes

Best Practices

Use List Item Shifter instead if you actually want items dropped or padded rather than wrapped around.
Remember N is taken modulo the list length, a very large N is safe and behaves the same as its remainder.

Developer Notes

The rotation amount is normalized with n % items.length before splitting the array into two slices and swapping their order, so both very large N values and the left/right direction toggle are handled by the same small formula rather than separate code paths.

List Rotator Use Cases

Cycling through a round-robin schedule of people, servers, or turns
Simulating a circular buffer or ring structure on a plain-text list
Generating every rotation of a fixed sequence for testing cyclic algorithms

Common Mistakes

Expecting items to be dropped like List Item Shifter; rotation always wraps them around instead.
Forgetting rotation amount is taken modulo the list length, so N and N + length produce identical results.
Mixing up left and right, left rotation moves the front items to the back; right rotation moves the back items to the front.

Tips

Rotate by the list's own length to confirm the tool correctly returns the list unchanged (a full cycle).
Use List Item Shifter instead whenever you specifically want items dropped rather than wrapped.

List Rotator