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Andrew Pandaleon
311 Pointsconstant vs. variable in dictionaries:
In the dictionaries challenge it has me identify the currencies dictionary as a let rather than a var. So when I enter currencies.removeValueForKey(UK") it comes up immutable.
Please advise.
let currencies = ["US": "Dollar", "UK": "Pound", "JP": "Yen"] let ukCurrencies = currencies.removeValueForKey("UK")
1 Answer
Jayden Spring
8,625 PointsLet is a constant, constants are immutable. You want a variable array i.e a var
Andrew Pandaleon
311 PointsI understand that. In the dictionaries challenge it requires you to create a constant dictionary called currencies. Then it requires you to change it and currencies.removeValueForKey to a new constant called ukCurrency. I'm wondering how to do this or if the challenge itself is flawed?
Jayden Spring
8,625 PointsIf you have a look at my screenshot here
The dictionary itself is mutable unless you want it to be immutable (ie fixed) so therefore is a var. You can then remove the key value pair and store the value to a constant.
Jayden Spring
8,625 PointsI have just looked at the challenge and it is not asking you to remove the item from the array but assign the value of 'UK' to a constant named uk currency.
Therefore all you need to do is let ukCurrency = currencies["UK"]
Andrew Pandaleon
311 PointsAndrew Pandaleon
311 PointsYes I get that the dictionary is a variable if its identified as such with var. However, it's a two part challenge. It will not let me complete the first part without assigning the dictionary as a constant. Therefore I cannot change it, as required, in the second part. This is maddening.