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Swift program to create a function with an in-out parameter

Here, we are going to learn how to create a function with an in-out parameter in Swift programming language?
Submitted by Nidhi, on June 24, 2021

Problem Solution:

Here, we will create a user-defined function with an in-out parameter. And, we used the inout keyword to get the updated value of the argument.

Program/Source Code:

The source code to create a function with an in-out parameter is given below. The given program is compiled and executed successfully.

// Swift program to create a function 
// with inout parameter

func updateValue(num: inout Int) {
  num = num + 10
}

var val = 5
print("Before: ", val)

updateValue(num: &val)

print("After: ", val)

Output:

Before:  5
After:  15

...Program finished with exit code 0
Press ENTER to exit console.

Explanation:

In the above program, we imported a package Swift to use the print() function using the below statement,

import Swift;

Here, we created a user-defined function updateValue(). The updateValue() function accepts a parameter with the inout keyword and updates the value of the argument and gets the updated value of the argument to the calling position. After that, we printed the result on the console screen.

Swift User-defined Functions Programs »

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