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iOS Intermediate Swift 2 Extensions and Protocols Extending a Native Type

can someone help me ?

i didn't understand what the task want from me .. add to that i didn't know how to know if the string contain an Int value or Not

extension String {
var add : Int {
if ()


1 Answer

The way to find out whether a string can be int is by using the conversion Int() and passing the string as an argument. If it returns nil, then it cannot be converted into a number otherwise it can. Something like this where you can then just add the number

var add: String{ If Int(self) != nil{ //assign the string to an integer constant and return the added expression } else{ return nil } }

Hope this helps!