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| function incrementListIndex(current, dir, opt) {
| var len = opt.choices.realLength;
| var shouldLoop = 'loop' in opt ? Boolean(opt.loop) : true;
| if (dir === 'up') {
| if (current > 0) {
| return current - 1;
| }
| return shouldLoop ? len - 1 : current;
| }
| if (dir === 'down') {
| if (current < len - 1) {
| return current + 1;
| }
| return shouldLoop ? 0 : current;
| }
| throw new Error('dir must be up or down');
| }
|
| module.exports = incrementListIndex;
|
|
