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Thomas Thomas
1,706 PointsHow do I assign a constant as part of a new key pair?
In the lesson it discussed dictionaries as variables, but in the challenge its asking for the dictionary to be made as a constant. I can't seem to figure out how to answer the question and I'm wondering if it's because the constant dictionary can't be changed?
9 Answers
Vittorio Somaschini
33,371 PointsExactly, you are not supposed to remove anything here Thomas.
Just declare a constant named ukCurrency, but without modifying the dictionary.
This will work:
let ukCurrency = currencies["UK"]
So that we retrieve the value associated to the "UK" key, but the dictionary stays as it is.
Hope it helped
Vittorio Somaschini
33,371 PointsHello Thomas.
I am not sure I understand your question properly but..
The challenge is simply asking you to create a dictionary and assign it to a constant (let), so:
let currencies =[]
Then, inside the [] you should put the keys with their relative values, for example:
"UK": "Pound"
That is all, I did not quiet understand the "assign a constant as part of a new key" part..
Vittorio Somaschini
33,371 PointsCan I see your code please?
Paste it here, because that code should not edit the dictionary anyhow (so the dictionary can be a constant with no problems), the code should only retrieve a value without "touching" the dictionary.
;)
Vittorio Somaschini
33,371 PointsAre you sure?
I have just copied and pasted your code + my code and it worked fine:
let currencies = [ "US":"Dollar", "UK":"Pound", "JP":"Yen"]
let ukCurrency = currencies["UK"]
Can you try copy/paste this?
Vittorio Somaschini
33,371 PointsI was going to guess something like that.
You should give me a best answer mark at least then!
ahah
;)
good luck
Thomas Thomas
1,706 PointsVittorio,
I am on the second part of the challenge where it's asking to:
"Assign the value for key "UK" to a constant named ukCurrency."
That's where it's stumping me. I've tried to do it on Xcode to see if I could resolve but I keep getting an error message of some sort telling me that I'm attempting to change an immutable value type. (because i made it a constant dictionary).
I'm sure I'm just missing something simple.
Thomas Thomas
1,706 PointsVittorio,
I am on the second part of the challenge where it's asking to:
"Assign the value for key "UK" to a constant named ukCurrency."
That's where it's stumping me. I've tried to do it on Xcode to see if I could resolve but I keep getting an error message of some sort telling me that I'm attempting to change an immutable value type. (because i made it a constant dictionary).
I'm sure I'm just missing something simple.
Thomas Thomas
1,706 Pointslet currencies = [ "US":"Dollar", "UK":"Pound", "JP":"Yen"]
let ukCurrency = currencies.removeValueForKey("UK")
Thomas Thomas
1,706 PointsSorry Vittorio, I was using () instead of []
Thank you so much for your help!!! You fixed about an hour of frustration!!