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iOS Swift Basics (retired) Types Printing Results

Posted by Hilda Joubert
Hilda Joubert
429 Points

My answer is correct

My answer for this task is: println("Learning " + language) But I get an error to interplate the constant "language".. but i do?????

println.swift 
let language : String = "Swift"

println("Learning " + language)

2 Answers

miguelcastro2
miguelcastro2
Courses Plus Student 6,573 Points

Your code is a good example of string concatenation, but for string interpolation Swift uses this format:

println("Learning \(language)")
Vivek Mitra
Vivek Mitra
2,051 Points
Vivek Mitra
Vivek Mitra
2,051 Points

Please recheck you output Hilda. It should work without an error.

let language : String = "Swift"

println("Learning " + language) // + operator

println("Learning \(language)") // String interpolation

Output:

Learning Swift

Learning Swift

This should work as in this both ways we can concatenate Strings, either using + operator or String interpolation

And the let (constant) here doesn't matter as we are not reassigning the value back to constant property language, when we concatenate the Strings here we are creating another New String in the heap.

language = Learning " + language // Error as language is a constant property