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in this example of GuidedTour of Swift by

https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/

var optionalString: String? = "Hello"
optionalString == nil 
var optionalName: String? = "John Appleseed"    
var greeting = "Hello!"

if let name = optionalName {
    greeting = "Hello, \(   name)"
}

I can not do this experiment, because of error

Change optionalName to nil. What greeting do you get? Add an else clause that sets a different greeting if optionalName is nil.

Bob Kaufman
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2 Answers2

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When I create new playground and enter exactly the same code you posted, it works. Can you post complete code ?

// Playground - noun: a place where people can play

import Foundation

var optionalString: String? = "Hello"
optionalString == nil
var optionalName: String? = "John Appleseed"
var greeting = "Hello!"
if let name = optionalName {
   greeting = "Hello, \(   name)"
}

Only thing which is different, seems that you forgot to import Foundation framework:

import Foundation
Sinisa Drpa
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  • could you please send me result of changes in that experiment? –  Jan 28 '15 at 17:49
  • No problem, here is the playground: http://www.tagtaxa.com/download/playground.zip – Sinisa Drpa Jan 28 '15 at 17:51
  • I mean result of this: Change optionalName to nil. What greeting do you get? Add an else clause that sets a different greeting if optionalName is nil. swift –  Jan 28 '15 at 17:53
  • Oh, sorry, if you change optionalName to nil you won't get greeting because optional unwrapping won't succeed. Look the example: http://www.tagtaxa.com/download/playground2.zip – Sinisa Drpa Jan 28 '15 at 17:57
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var optionalString: String? = "Hello"
print(optionalString == nil)



var optionalName: String? = nil
var greeting = "Hello!"
if let name = optionalName {
    greeting = "Hello, \(name)"
}else{
    greeting = "Hello Max"
}
greeting
fresno
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