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

Brendan McCarthy
Brendan McCarthy
2,854 Points
Posted by Brendan McCarthy
Brendan McCarthy
2,854 Points

This Challenge wants me to assign a value for a key from an immutable index.

How can I assign "ukCurrency" if the Challenge won't let me assign "currencies" as a variable instead of a constant?

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

let ukCurrency = currencies.removeValueForKey("UK")

1 Answer

Michael Hulet
Michael Hulet
47,913 Points
Michael Hulet
Michael Hulet
47,913 Points

You don't want to change the value of the currencies Dictionary at all (removeValueForKey simply takes the item at that key out of the Dictionary). Instead, you just want to copy the value associated with the key "UK" from the currencies Dictionary. You'd do that with simple subscript syntax, like this:

let ukCurrency = currencies["UK"]