Please note that empty slots are different from slots filled with the value undefined. Similarly, when you delete an element from an array, it leaves holes (or creates empty slots) in the array, making it sparse: directly setting a slot with index greater than `array.length`: directly setting `array.length` greater than total array elements: You can see this demonstrated in the following examples, where a sparse is created by setting a larger length than the number of elements the array has:Ĭonsole.log() // Similarly, when you extend an array by modifying it's length without adding a new element, it too creates empty slots (as the indexes don't point to any element yet). Deleting an item from such a collection, does not automatically re-index the array, thus leaving holes/gaps in it instead. This happens because arrays are indexed collection, where each element appears in a set sequence. When elements are deleted from an array.When an array is created with a length that is larger than the number of elements that it initially contains, or.
A sparse array in JavaScript refers to an array that has one or more empty slots (or 'holes') in it.
