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iOS

Posted by Anthia Tillbury
Anthia Tillbury
3,388 Points

Difference between mutating an array and appending?

In the video "Reading and Modifying an Array" it was shown how to mutate an array to insert a new string literal to an array, at a certain position and shift the existing contents along:

todo[4] = "Brush teeth

But in the following video "Inserting and Deleting Values" the insert method is used to achieve the same thing: 

todo.insert("Watch TV", at: 2)

2 Answers

Alexander Davison
Alexander Davison
65,469 Points

This:

todo[4] = "Brush teeth

Actually modifies the element if the element exists.

This:

todo.insert("Watch TV", at: 2)

Adds an element at a particular index, but doesn't modify

I hope this helped :grin:

Happy C0D1NG! :tada:

:dizzy: ~Alex :dizzy:

Anthia Tillbury
Anthia Tillbury
3,388 Points
Anthia Tillbury
Anthia Tillbury
3,388 Points

I see, so the first example replaces.