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

Posted by Zyad Gomaa
Zyad Gomaa
252 Points

I’m not sure what i’m doing wrong

my code follows the video’s instructions, so i’m not sure why it’s wrong

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

let ukCurrency = currencies.removeValueForKey ("UK")

2 Answers

kjvswift93
kjvswift93
13,515 Points
kjvswift93
kjvswift93
13,515 Points

The reason this is not working is because currencies has been declared as a constant, and therefore cannot be mutated, which you attempt to do by using 'removeValueForKey'. To pass the challenge, you need to capture a value within the dictionary, not change the dictionary. It should look like this:

let currencies = ["US":"Dollar",
                  "UK":"Pound",
                  "JP":"Yen"]

let ukCurrency = currencies["UK"]
Stefan Jansen
Stefan Jansen
1,515 Points
Stefan Jansen
Stefan Jansen
1,515 Points

You used the Let statement, you can't change the value of a let statement The only thing you need to do is to replace the first "let" with "var"