Usually it’s a contiguous section (but see the step parameter for an exception to that rule). Slicing and SplicingĪ slice is a section of an array or list. As we’ll see, there are some differences in the syntax used for splicing and splicing, but also a lot of similarities in how slicing and splicing work in the two languages. The differences between the structures they allow, such as that JavaScript arrays can be sparse, while Python’s lists don’t allow this, are beyond the scope of this post. They’re both loosely typed sequences of items, indexed by sequential integers starting at 0, with the ability to add or remove items at any point (in other words, they’re not a fixed length). Lists in Python and arrays in JavaScript are built-in data structures that are used for mostly equivalent things. This is intended as a map between the two languages, rather than a comparison of their strengths and weaknesses. This post covers some of the syntax and parameters for doing array or list slices and splices in Python and JavaScript - in other words, working with sections of lists or arrays, instead of the whole list/array - and some of the similarities and differences between them.

Array slice in javascript