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 * Move an item from one index to another in an array.
 * (c) 2020 Chris Ferdinandi, MIT License,
 * @param  {Array}   arr  The array to move the item in
 * @param  {Integer} from The starting index of the item
 * @param  {Integer} to   The new index for the item
var moveInArray = function (arr, from, to) {

	// Make sure a valid array is provided
	if ( !== '[object Array]') {
		throw new Error('Please provide a valid array');

	// Delete the item from it's current position
	var item = arr.splice(from, 1);

	// Make sure there's an item to move
	if (!item.length) {
		throw new Error('There is no item in the array at index ' + from);

	// Move the item to its new position
	arr.splice(to, 0, item[0]);


// Sandwiches array
var sandwiches = ['ham', 'tuna', 'turkey', 'pb&j'];

// Move 'turkey' to the first spot in the array
moveInArray(sandwiches, 2, 0);