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

Posted by Jaen Rivera
Jaen Rivera
774 Points

Hi, how can I change the value of a constant?

If I try let ukCurrency = currencies.removeValueForKey("UK")

it's not possible because I already have currencies as a constant.

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

2 Answers

Cameron Armstrong
Cameron Armstrong
9,406 Points
Cameron Armstrong
Cameron Armstrong
9,406 Points

Then make it a variable instead of a constant. Constants by definition are... well.. constant. They don't change.

Replace the "let" with "var"

Jaen Rivera
Jaen Rivera
774 Points
Jaen Rivera
Jaen Rivera
774 Points

Yeah, I was trying to, but I had to keep currencies as a constant, my approach was incorrect. Instead I use another way to reassign the value from the dictionary.

let ukCurrency = currencies["UK"]

Thanks