do-while

More often than not we need loops like this do { Type value(GetCurrentValue()); Process(value); }while(condition(value)); Unfortunately this will not compile, because value 's scope ends at } . Which means that I will have to declare it outside the loop. Type value; do { value = GetCurrentValue(); Process(value); }while(condition(value)); I don't like this for at least two reasons. For one, I like declaring things locally. And second, this is a problem if value is not assignable or default-constructible, but only copy-constructible. So, my question has two sides. First, I'd like to know if

I'm writing this program in java where I need to re-prompt the user after an invalid input. I came to a solution only to discover that if the user enters another invalid input after the re-prompt then it continues. Can someone please show me a better solution to this? I'll show you what I had anyway: System.out.println("What is your age?\n"); age = userInput.nextInt(); if((age > 120) || (age < 1)) {//error message System.out.println("ERROR Please enter a valid age"); System.out.println(""); System.out.println("What is your age?\n"); age = userInput.nextInt(); }//end if if the user entered an

I have profiled for , while and do-while loops with something simple: while ($var < 1000000) { ++$var; } do { ++$var; } while ($var < 1000000); for ($var = 0; $var < 1000000; ++$var) { //do nothing } by comparing microtime() before and after the loops. The do-while loop is by a considerable amount the fastest loop. do-while is actually faster than while by almost half. I know that they are for different purposes ( while checks the condition before the loop executes and do-while executes at least once ). I know the general consensus is that while loops are frowned upon and do-while even more so

I would like to create a stored routine for MySQL that figures out the number of business or working days for a month (Working Days are Monday thru Friday). It's a syntax error however I don't know what the syntax error is. All it tells me is: 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'WHILE(@daycount < @totaldays) DO IF (WEEKDAY(@checkweekday) < 6) THEN ' at line 2 My Syntax Error is in the following: WHILE(@daycount < @totaldays) DO IF (WEEKDAY(@checkweekday) < 6) THEN My Code: SELECT MONTH

How to do code something like this in groovy ? do { x.doIt() } while (!x.isFinished()) Because there is no do ... while syntax in groovy. No 'do ... while()' syntax as yet. Due to ambiguity, we've not yet added support for do .. while to Groovy References: groovy - dev > do while Migration From Classic to JSR syntax Groovy Documentation > Control Structures > Looping Rosetta Code > Loops/Do-while Groovy So many answers and not a single one without a redundant call, a shame ;) This is the closest it can get to purely language syntax based do-while in Groovy: while ({ x.doIt() !x.isFinished() }(

To start with I'll say that I agree that goto statements are largely made irrelevant by higher level constructs in modern programming languages and shouldn't be used when a suitable substitute is available. I was re-reading an original edition of Steve McConnell's Code Complete recently and had forgotten about his suggestion for a common coding problem. I had read it years ago when I was first getting started and don't think I realized how useful the recipe would be. The coding problem is the following: when executing a loop you often need to execute part of the loop to initialize state and

When I was taking CS in college (mid 80's), one of the ideas that was constantly repeated was to always write loops which test at the top (while...) rather than at the bottom (do ... while) of the loop. These notions were often backed up with references to studies which showed that loops which tested at the top were statistically much more likely to be correct than their bottom-testing counterparts. As a result, I almost always write loops which test at the top. I don't do it if it introduces extra complexity in the code, but that case seems rare. I notice that some programmers tend to almost