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iOS Swift Basics (retired) Types Printing Results

Posted by Abdullah Alsowaygh
Abdullah Alsowaygh
8,719 Points

I don't understand the interpolation part. In other programming languages I can print two string using + between them

I don't understand the interpolation part. In other programming languages such as C++ or java I can print two string using + between their names. for example

println (greeting + language)

and if one of the values of the variables is changed then it is also changed in the print statement.

println.swift 
let language = "Swift"

var greeting = "Hello "

println (/greeting  /language)

2 Answers

Nathan F.
Nathan F.
30,773 Points
Nathan F.
Nathan F.
30,773 Points

Those are actually different (but related) features--concatenation and interpolation.

Interpolation allows you to put a variable directly inside of a string, where concat can achieve the same affect by stringing together strings and variables.

You can still actually add strings together. For example:

let myString = "Hello"
let otherString = "World"
let message = myString + otherString
let readableMessage = myString + " " + otherString
print(message)
print(readableMessage)

"HelloWorld"
"Hello World"

Also to interpolate, your syntax needs a fix:

println("\(language) \(greeting)")
Abdullah Alsowaygh
Abdullah Alsowaygh
8,719 Points

Yes I have noticed that I have syntax errors. But your explanation helped make things clearer.

Thank you very much!

kjvswift93
kjvswift93
13,515 Points
kjvswift93
kjvswift93
13,515 Points

All you need to do to print out "Learning Swift" using the constant named language is this: 

let language = "Swift"
println("Learning \(language)")