while-loop

I try to make CasperJS achieve the following: Go through a series of pages that are named sequentially by date. On each page, locate a PDF link. Download the PDF. I got some working code, but I don't understand how CasperJS is going through the sequence of events. For instance, in the code sample below, CasperJS tries to process step 2, and throws a "ReferenceError: Can't find variable: formDate", while step 1 isn't executed at all for some reason. What's wrong with my reasoning? It seems to me that the while loop is executed at a different speed than the casper.then methods. casper.start();

Let's say I have this: while(a){ while(b){ if(b == 10) break; } } Question: Will the break statement take me out of both loops or only from the inner one? Thank you. Abhishekkumar In your example break statement will take you out of while(b) loop while(a) { while(b) { if(b == 10) { break; } } // break will take you here. } Ivan Koblik It will break only the most immediate while loop. Using a label you can break out of both loops: take a look at this example taken from here public class Test { public static void main(String[] args) { outerloop: for (int i=0; i < 5; i++) { for (int j=0; j < 5; j

I just came across this piece of code while 1: line = data.readline() if not line: break #... and thought, there must be a better way to do this, than using an infinite loop with break . So I tried: while line = data.readline(): #... and, obviously, got an error. Is there any way to avoid using a break in that situation? Edit: Ideally, you'd want to avoid saying readline twice... IMHO, repeating is even worse than just a break , especially if the statement is complex. If you aren't doing anything fancier with data, like reading more lines later on, there's always: for line in data: ... do

I run into this case a lot of times when doing simple text processing and print statements where I am looping over a collection and I want to special case the last element (for example every normal element will be comma separated except for the last case). Is there some best practice idiom or elegant form that doesn't require duplicating code or shoving in an if, else in the loop. For example I have a list of strings that I want to print in a comma separated list. (the do while solution already assumes the list has 2 or more elements otherwise it'd be just as bad as the more correct for loop

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