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

Josh Schlabach
Josh Schlabach
1,771 Points
Posted by Josh Schlabach
Josh Schlabach
1,771 Points

I'm trying out the 2nd dictionary challenge but this pops up in the output:

swift_lint.swift:4:18: error: immutable value of type '[String : String]' only has mutating members named 'removeValueForKey' let ukCurrency = currencies.removeValueForKey("UK")

1 Answer

johanneseichler
johanneseichler
6,514 Points
johanneseichler
johanneseichler
6,514 Points

If I have seen this correctly you are asked to assign the value of the key "UK" to the constant. But you tried to assign the value to the constant and remove it. As "currencies" is a constant (created with "let") it is immutable and you cannot remove any values.

The correct way to assign a value from a dictionary is

nameOfTheDictionary[key]

in this case

ukCurrency = currencies["UK"]