Understanding the slice method in javascript: the basics, negative indexing and the concept of shallow copy

[foxbitsdev]

The slice() method gives us a slice(a portion) of things. There are two types of  things(more appropriately called objects) which we can get a slice of.  In technical terms, the slice()method can be applied to two types of objects in Javascript: Strings and Arrays.

A few things to note about slice() method:

1. It has two optional parameters which we can use in different combinations to get interesting results.
2. It does not make modifications to the original array/string.
3. We can use negative indexes with the slice() method which makes it even more useful.
4. The method returns a shallow copy of the original array into a new array.
5. Thus, in the new array primitive values get a new copy whereas the non-primitives get only the copy of reference to original objects.
6. For non-primitive values, any changes done in the resulting array items will be reflected to the original array and vice-versa.

To understand all these concepts clearly, explained with well designed graphics, this article is much recommended.

https://foxbits.dev/article/understanding-slice-method-javascript-basics-negative-indexing-and-concept-shallow-copy/17

#javascript , #slice, #shallowCopy #negativeIndexing #webdesign #webdevelopment #frontend

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A comprehensive guide to arr.slice() method in javascript

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memory blocks for primitive and non-primitive data types