Returning Reference from Swift Function

Question

veer_dutta07 OP

Created Sep ’24

Replies 2

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Participants 3

I have a use case where I want to return reference from Swift Function just like we can do in C++.

This is How we do it in C++:


int & ReturnIntRef () noexcept
{
      static int a  = 4;

      return a;
}

Do we have equivalent of this in Swift ?

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Answer 1

Claude31 OP

Sep ’24

You seem to have a major concern with reference values. What is the main issue you have ?

As a general comment, you should avoid trying to replicate exactly C++ patterns into Swift. Some logics (notably about types, memory management…) are pretty different and it may be risky with dangerous side effects. https://stackoverflow.com/questions/752658/is-the-practice-of-returning-a-c-reference-variable-evil

In your example, what is the purpose of noexcept here ?

Are you sure it is correct ?

int & ReturnIntRef ()

It should be

int& ReturnIntRef ()

Similar pattern in Swift would not work, as the var a would be deleted when exiting the function, unless you use an escaping closure, but that may be overkill.

There are several ways to do what you want.

A simple one, as I answered in another post is to call parameter as inout.
you can also declare a class type that holds the parameter
use pointers, at your own risks, as described in detail here: https://stackoverflow.com/questions/27539533/how-to-return-an-inout-reference-in-a-swift-function

1

Answer 2

endecotp OP

Sep ’24

Are you trying to implement a singleton?

1