Search results
Results from the WOW.Com Content Network
In many computer programming languages, a do while loop is a control flow statement that executes a block of code and then either repeats the block or exits the loop depending on a given boolean condition. The do while construct consists of a process symbol and a condition. First the code within the block is executed.
In the C programming language, Duff's device is a way of manually implementing loop unrolling by interleaving two syntactic constructs of C: the do-while loop and a switch statement. Its discovery is credited to Tom Duff in November 1983, when Duff was working for Lucasfilm and used it to speed up a real-time animation program.
Compare this with the do while loop, which tests the condition/expression after the loop has executed. For example, in the languages C , Java , C# , [ 2 ] Objective-C , and C++ , (which use the same syntax in this case), the code fragment
If xxx1 is omitted, we get a loop with the test at the top (a traditional while loop). If xxx2 is omitted, we get a loop with the test at the bottom, equivalent to a do while loop in many languages. If while is omitted, we get an infinite loop. The construction here can be thought of as a do loop with the while check in the middle. Hence this ...
A conditional loop has the potential to become an infinite loop when nothing in the loop's body can affect the outcome of the loop's conditional statement. However, infinite loops can sometimes be used purposely, often with an exit from the loop built into the loop implementation for every computer language, but many share the same basic ...
In computer programming, foreach loop (or for-each loop) is a control flow statement for traversing items in a collection. foreach is usually used in place of a standard for loop statement . Unlike other for loop constructs, however, foreach loops [ 1 ] usually maintain no explicit counter: they essentially say "do this to everything in this ...
Do While condition instructions Loop or Do Until notcondition instructions Loop or While condition instructions Wend (Visual Basic .NET uses End While instead) Do instructions Loop While condition or Do instructions Loop Until notcondition: i must be declared beforehand. For i = first To last «Step 1» instructions Next i. For Each item In set
ALGOL 68 has what was considered the universal loop, the full syntax is: FOR i FROM 1 BY 2 TO 3 WHILE i≠4 DO ~ OD Further, the single iteration range could be replaced by a list of such ranges. There are several unusual aspects of the construct only the do ~ od portion was compulsory, in which case the loop will iterate indefinitely.