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JavaScript

brandonlind2
brandonlind2
7,823 Points
Posted by brandonlind2
brandonlind2
7,823 Points

can someone explain these []?

I'm seeing alot of square brackets within functions parentheses on mdn, but I'm not sure what they mean? for example

array.splice(start, deleteCount[, item1[, item2[, ...]]])

1 Answer

Steven Parker
Steven Parker
230,879 Points
Steven Parker
Steven Parker
230,879 Points

As used in documentation, they mean "optional". So for your example:

array.splice(start, deleteCount[, item1[, item2[, ...]]])

This shows that the splice method can take as few as 2 arguments (start and deleteCount), but it can take more (items to be added), with no obvious limit.