A while loop will always evaluate the condition first. while (condition) { //gets executed after condition is checked } A do/while loop will always execute the code in the do{} block first and then evaluate the condition. do { //gets executed at least once } while (condition); A for loop allows you to initiate a … Read more
Starting Python 3.8, and the introduction of assignment expressions (PEP 572) (:= operator), it’s now possible to capture the condition value (data.readline()) of the while loop as a variable (line) in order to re-use it within the body of the loop: while line := data.readline(): do_smthg(line)
Oneliner 🙂 while (e.InnerException != null) e = e.InnerException; Obviously, you can’t make it any simpler. As said in this answer by Glenn McElhoe, it’s the only reliable way.
Use break: while (true) { …. if (obj == null) { break; } …. } However, if your code looks exactly like you have specified you can use a normal while loop and change the condition to obj != null: while (obj != null) { …. }
The correct notation for Process Substitution is: while read i; do echo $i; done < <(echo “$FILECONTENT”) The last value of i assigned in the loop is then available when the loop terminates. An alternative is: echo $FILECONTENT | { while read i; do echo $i; done …do other things using $i here… } The … Read more
The advantage of TimerTask is that it expresses your intention much better (i.e. code readability), and it already has the cancel() feature implemented. Note that it can be written in a shorter form as well as your own example: Timer uploadCheckerTimer = new Timer(true); uploadCheckerTimer.scheduleAtFixedRate( new TimerTask() { public void run() { NewUploadServer.getInstance().checkAndUploadFiles(); } }, … Read more
If you always want the loop to execute at least once. It’s not common, but I do use it from time to time. One case where you might want to use it is trying to access a resource that could require a retry, e.g. do { try to access resource… put up message box with … Read more
The easiest way is to just interrupt it with the usual Ctrl-C (SIGINT). try: while True: do_something() except KeyboardInterrupt: pass Since Ctrl-C causes KeyboardInterrupt to be raised, just catch it outside the loop and ignore it.
A While/Wend loop can only be exited prematurely with a GOTO or by exiting from an outer block (Exit sub/function or another exitable loop) Change to a Do loop instead: Do While True count = count + 1 If count = 10 Then Exit Do End If Loop Or for looping a set number of … Read more
The problem in this particular case is that you return from within the for-expression. That in turn gets translated into a throw of a NonLocalReturnException, which is caught at the enclosing method. The optimizer can eliminate the foreach but cannot yet eliminate the throw/catch. And throw/catch is expensive. But since such nested returns are rare … Read more