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iOS Swift Basics (retired) Types Strings

Posted by James R
James R
Courses Plus Student 8,446 Points

String Interpolation ?

Is String Interpolation the sane as using #DEFINE in C ? Can someone please give me a real world example on why using ("stringName") is useful in Swift ?

1 Answer

Jennifer Nordell
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Jennifer Nordell
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Jennifer Nordell
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Jennifer Nordell
Treehouse Teacher

Ok you're familiar with old school C I take it. So remember the old printf statements before cin and cout in C++? String interpolation is a little like this. 

printf("2 * 3 is  %d", 2*3);

So it will print out "2 * 3 is 6". That's string interpolation at its core. Take the same example in Swift.

let x = 2
let y = 3
let result = x*y

print("\(x) * \(y) is \(result)"

This works a bit like the %d etc that you're used to in C except that it inserts the value of that variable in that place. Hope that's helpful!

James R
James R
Courses Plus Student 8,446 Points

makes sense.. using this instead of tokens like %d %i etc etc ...

Thanks !

Jennifer Nordell
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Jennifer Nordell
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Jennifer Nordell
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Jennifer Nordell
Treehouse Teacher

James Richardson Exactly! Except that now you don't have to know what data type it is :smiley: Whatever that value is for that variable will be inserted there. That's also true for lists and arrays if you give the index.