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

Oleg Shamin
Oleg Shamin
1,798 Points
Posted by Oleg Shamin
Oleg Shamin
1,798 Points

Hello. How I can finish this challenge, if it has an error every time? I think,I must print "var currencies", not "let"

When I trying finished 2 object, I have an error every time. I think its because I use "var currencies", but not "let currencies"

dictionaries.swift

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

it needs to be let

task 2 states: Assign the value for key "UK" to a constant named ukCurrency.

you dont change the value assigned to the key "UK", you assign the value of that key to a new constant:

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

let ukCurrency = currencies["UK"] // ukCurrency now has a value of "Pound"
// currencies remains unchanged, with a value of [ "US": "Dollar", "UK": "Pound", "JP": "Yen"]

this does not modify the currencies dict at all, you just access a value from it. nothing in the dictionary changes. you are basically saying "give me the value that corresponds to this key, and assign that value to this constant". it doesnt change anything about the dictionary itself