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

Posted by Brandon Meeks
Brandon Meeks
Courses Plus Student 925 Points

I'm struggling on this code challenge. You can't remove anything from a constant

I created the dictionary as the challenge requested. Now it's wanting me to remove a key and assign it to a new constant. However, you can't edit a constant. Hence my confusion on how to pass this.

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

2 Answers

B B
B B
2,934 Points
B B
B B
2,934 Points

I believe it just asks you to assign the UK currency to a constant, so you just need to do a let statement = the dictionary entry for UK currency using the correct syntax.

Dennis Parussini
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Dennis Parussini
Treehouse Project Reviewer
Dennis Parussini
.a{fill-rule:evenodd;}techdegree seal-36
Dennis Parussini
Treehouse Project Reviewer

The actual answer isn't to remove the value from the dictionary, but to assign a given value from the dictionary to a new constant. So the right answer would be

let currencies = ["US": "Dollar", "UK": "Pound", "JP": "Yen"]
let ukCurrency = currencies["UK"]
Curtis Curry
Curtis Curry
717 Points
Curtis Curry
Curtis Curry
717 Points

That did not seem to work for me so I tried to do it like this and am still getting an error: Bummer! You need have let ukCurrency defined.

Here is my code:

// Code Country Code // or // Key Value // US Dollar // UK Pound // JP Yen

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

let ukCurrencies = currencies["UK"]

Curtis Curry
Curtis Curry
717 Points
Curtis Curry
Curtis Curry
717 Points

AND apparently I don't know how to post my code and make it look all pretty like you guys. I read the Markdown stuff but it isn't making sense.

Dennis Parussini
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Dennis Parussini
Treehouse Project Reviewer
Dennis Parussini
.a{fill-rule:evenodd;}techdegree seal-36
Dennis Parussini
Treehouse Project Reviewer

@Curtis: You have a typo.

The challenge says you have to assign it to let ukCurrency, not let ukCurrencies.

Curtis Curry
Curtis Curry
717 Points
Curtis Curry
Curtis Curry
717 Points

Oh yeah, I had ukCurrencies and changed it to ukCurrency and it worked. I copied/pasted from your example above. For other users: don't be like me, don't copy and paste! It's a trap! :)

No, but seriously, maybe we can edit the code in your answer above. Thanks for the response!