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iOS Swift Basics (retired) Collections Modifying an Array

Posted by James Louis
James Louis
Courses Plus Student 924 Points

with the todo.insert I'm not sure what I'm doing wrong

need help with todo.insert array

arrays.swift 
var todo = ["Learn Swift", "Build App", "Deploy App"]
todo.append("Debug App")
todo.append("Fix Bugs")
let item = todo.removeAtIndex
todo.insert("Learn iOS", atIndex: 2)

3 Answers

Marc Biggar
Marc Biggar
10,942 Points
Marc Biggar
Marc Biggar
10,942 Points

Just need to modify your atIndex: 2 to show atIndex: 1.

Remembering that indexes start at 0

Grant Williamson
Grant Williamson
1,622 Points
Grant Williamson
Grant Williamson
1,622 Points

You're adding the "Learn iOS" string at index 2. Remembering that arrays start from 0, it will look something like this:

0 => Learn Swift
1 => Build App
2 => Learn iOS // Added with insert function. What was here will be moved down one place.
3 => Deploy App
4 => Debug App
5 => Fix Bugs
Julian Scharf
Julian Scharf
2,007 Points
Julian Scharf
Julian Scharf
2,007 Points

I have a related question about the syntax of this function.

This is what I see in the IDE autocomplete: todo.insert(newElement: Element, atIndex: Int)

typing atIndex: is mandatory

why don't we also need to type in newElement:?