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iOS Error Handling in Swift 2.0 Error Handling Modeling Errors

Jacob Swedenburg
Jacob Swedenburg
252 Points
Posted by Jacob Swedenburg
Jacob Swedenburg
252 Points

Why are you unwrapping types that are not optionals?

Why are you checking to see if name and age values exist if they are not declared as optionals? This seems backwards to me. Shouldn't you unwrap the optional type, not the non-optionals?

Lukas G.
Lukas G.
4,842 Points
Lukas G.
Lukas G.
4,842 Points

If you get data from a dictionary, it's always an optional, since it's possible that no value exists for the key you provided. In this case Nil is returned and only Optionals can store the value Nil. 

let someDict = ["A": "a", "B": "b"]

let someValue = someDict["A"]
let otherValue = someDict["C"]

someValue = optional("A") otherValue = Nil

In the friend struct "name " and "age" are not allowed to be Nil, since they are not of type optional. There is no need to unwrap address (of type optionalString), since we don't care what it stores, because even Nil is ok.