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iOS

Posted by jon kelson
jon kelson
5,149 Points

trying to work out reason for printing one part of code and not the other

import UIKit

var str : String = "Hello " let modernProgrammingLanguage: String = "Swift"

var greeting = "(str)(modernProgrammingLanguage)"// implicit type or inferred type println("To build an iphone app we learn (modernProgrammingLanguage)" )

//Question //This above will print out "To build an iPhone app we learn Swift"

I'm confused , why does it not print of the str "Hello" so it would read "Hello Swift" because the var greeting is asking for str ("Hello") and modernProgrammingLanguage("swift") ?

jon kelson
jon kelson
5,149 Points

sorry when i posted the question it squashed the code up above .

2 Answers

Fernando Claussen
Fernando Claussen
9,324 Points

You are assigning Hello Swift to a variable called greeting. That variable is not being used anywhere. On your println you are not using that "greeting" variable.

jon kelson
jon kelson
5,149 Points

Thank you Fernando, I can see that now the println is doing the work . So my other question would be is why were we asked to input the line of code

var greeting = "\ (str)\ (modernProgrammingLanguage)"

what does that line of code do if this isn't being used. ?.

or were they just showing that would be a good line of code if you wanted to print out "Hello Swift" ? by using

println "(str)(modernProgrammingLanguage)"

to get "Hello Swift"

ps excuse that lack of backslash the computer removes them as soon as I post .

jon kelson
jon kelson
5,149 Points

Thank you it all makes sense now .

Mark Cranston
Mark Cranston
1,817 Points
Mark Cranston
Mark Cranston
1,817 Points

I think you may have forgotten you backslash for the string interpolation.

var str : String = "Hello " 
let modernProgrammingLanguage: String = "Swift"

var greeting = "\(str)\(modernProgrammingLanguage)"
jon kelson
jon kelson
5,149 Points

Sorry mark and thank you yes I did miss out the backlash . But the main question was I was confused as to why the code prints of the lower println code and not the str "Hello" .