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iOS Swift 2.0 Collections and Control Flow Dictionaries Modifying a Dictionary

Mert Kahraman
Mert Kahraman
12,118 Points
Posted by Mert Kahraman
Mert Kahraman
12,118 Points

How do we change the existing keys without changing their values?

We saw how to change the values for certain keys, but is there a way to directly change the key of a value as well? For example, can we change the key value pair "LGA" : "La Guardia" to "ABC" : "La Guardia" directly? Or do we need to delete the LGA one and add the ABC one?

2 Answers

Michael Hulet
Michael Hulet
47,912 Points
Michael Hulet
Michael Hulet
47,912 Points

A dictionary maintains a relationship between a key and a value, but not between a value and a key. In other words, while there may be a valueForKey: method, there's no keyForValue: method, because keys can't be referenced by their value. Thus, the only way that's possible is the second method you described

Michael Hulet
Michael Hulet
47,912 Points
Michael Hulet
Michael Hulet
47,912 Points

FYI: Your answer is in Python, but the question is in Swift