export function findItemAndDelete(array, predicate) { return deleteAtIndex(array, array.findIndex(predicate)); } export function addItem(array, item) { const index = array.indexOf(item); if (index > -1) return false; array.push(item); return true; } export function deleteItem(array, item) { return deleteAtIndex(array, array.indexOf(item)); } export function deleteItems(array, ...items) { for (let item of items) { deleteItem(array, item); } } export function findById(array, id) { if (!array) return false; return array.find((item) => item.id === id); } export function hasItem(array, item) { if (!array) return false; return array.indexOf(item) > -1; } function deleteAtIndex(array, index) { if (index === -1) return false; array.splice(index, 1); return true; }