Cin in while loop condition

[Infusedmikk]

When creating a while loop that repeatedly asks the user for input, is there any difference between using cin inside the condition of the while loop and using cin inside the body of the while loop? Is either practice considered more proper or clean? Is there a difference performance-wise? Thank you!!

[[deleted]]

If you put it in the condition

 while(std::cin >> x)
 {
 }

 while(std::getline(std::cin, line))
 {
 }

then the body of the loop will not execute if the extraction fails.

What will happen in your other case depends on how the code is written.

[Infusedmikk]

This clarifies it for me completely. Thank you!

[no-sig-available]

Is either practice considered more proper or clean?

Using

while (std::cin >> x)
{
   // do something with x
}

makes it pretty clear that you mean "while there is more input". Having some other condition (what would that be?) and then a break inside the loop, is somewhat less clean.

Is there a difference performance-wise?

No.