Question

I often use this code pattern:

while(true) {      //do something      if(<some condition>) {         break;     }  }    

Another programmer told me that this was bad practice and that I should replace it with the more standard:

while(!<some condition>) {      //do something  }    

His reasoning was that you could ‘forget the break’ too easily and have an endless loop. I told him that in the second example you could just as easily put in a condition which never returned true and so just as easily have an endless loop, so both are equally valid practices.

Further, I often prefer the former as it makes the code easier to read when you have multiple break points, i.e. multiple conditions which get out of the loop.

Can anyone enrichen this argument by adding evidence for one side or the other?

Answer 1

There is a discrepancy between the two examples. The first will execute the ‘do something’ at least once every time even if the statement is never true. The second will only ‘do something’ when the statement evaluates to true.

I think what you are looking for is a do-while loop. I 100% agree that while (true) is not a good idea because it makes it hard to maintain this code and the way you are escaping the loop is very goto esque which is considered bad practice.

Try:

do {   //do something } while (!something); 

Check your individual language documentation for the exact syntax. But look at this code, it basically does what is in the do, then checks the while portion to see if it should do it again.