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iOS Swift Basics (retired) Collections What is a Dictionary?

Posted by Malthe Pedersen
Malthe Pedersen
2,338 Points

It really frustrates me, that I am not able to do this!!!!!!!!!!!!!!!! I do not understand your errors!

I cannot assign the value of UK to a constant named ukCurrency....................

dictionaries.swift 
let currencies = [ "US": "Dollar", "UK": "Pound", "JP": "Yen"]
let ukCurrency = currencies.removeValueForKey("UK")
ukCurrency

3 Answers

kjvswift93
kjvswift93
13,515 Points 
let currencies = ["US": "Dollar", "UK": "Pound", "JP": "Yen"]
let ukCurrency = currencies["UK"]

This is the correct answer for the challenge.

Rob Watts
Rob Watts
2,739 Points
Rob Watts
Rob Watts
2,739 Points

You almost had this right: your initial array, currencies, was declared as a constant. Constants are not mutable, therefore you cannot use the removeValueForKey method. Change your "let" to "var" and it will work.

Malthe Pedersen
Malthe Pedersen
2,338 Points
Malthe Pedersen
Malthe Pedersen
2,338 Points

Unfortunaly not, I already tried that, then it says something about, that it needs to be a constant not a variable

Rob Watts
Rob Watts
2,739 Points

Really? Take a look at this screenshot. It's working in my playground: https://dl.dropboxusercontent.com/u/526349/swift.png