AFAIK, there are two approaches: Iterate over a copy of the collection Use the iterator of the actual collection For instance, List<Foo> fooListCopy = new ArrayList<Foo>(fooList); for(Foo foo : fooListCopy){ // modify actual fooList } and Iterator<Foo> itr = fooList.iterator(); while(itr.hasNext()){ // modify actual fooList using itr.remove() } Are there any reasons to prefer one … Read more
How can I loop through a std::map in C++? My map is defined as: std::map< std::string, std::map<std::string, std::string> > For example, the above container holds data like this: m[“name1”][“value1”] = “data1”; m[“name1”][“value2”] = “data2”; m[“name2”][“value1”] = “data1”; m[“name2”][“value2”] = “data2”; m[“name3”][“value1”] = “data1”; m[“name3”][“value2”] = “data2”; How can I loop through this map and access … Read more
I want to cycle through the objects contained in an array and change the properties of each one. If I do this: for (var j = 0; j < myArray.length; j++){ console.log(myArray[j]); } The console should bring up every object in the array, right? But in fact it only displays the first object. if I … Read more
I have a div and it has several input elements in it… I’d like to iterate through each of those elements. Ideas? 8 Answers 8
I know that recursion is sometimes a lot cleaner than looping, and I’m not asking anything about when I should use recursion over iteration, I know there are lots of questions about that already. What I’m asking is, is recursion ever faster than a loop? To me it seems like, you would always be able … Read more
This question already has answers here: Equivalent of “continue” in Ruby (7 answers) Closed 5 years ago. In Ruby, how do I skip a loop in a .each loop, similar to continue in other languages? 2 Answers 2
I’ve used recursion quite a lot on my many years of programming to solve simple problems, but I’m fully aware that sometimes you need iteration due to memory/speed problems. So, sometime in the very far past I went to try and find if there existed any “pattern” or text-book way of transforming a common recursion … Read more
Some ways to iterate through the characters of a string in Java are: Using StringTokenizer? Converting the String to a char[] and iterating over that. What is the easiest/best/most correct way to iterate? 16 Answers 16
I’m trying to iterate through an array of elements. jQuery’s documentation says: jquery.Each() documentation Returning non-false is the same as a continue statement in a for loop, it will skip immediately to the next iteration. I’ve tried calling ‘return non-false;’ and ‘non-false;’ (sans return) neither of which skip to the next iteration. Instead, they break … Read more
I’m looking for the standard idiom to iterate over an NSArray. My code needs to be suitable for OS X 10.4+. 8 Answers 8 The generally-preferred code for 10.5+/iOS. for (id object in array) { // do something with object } This construct is used to enumerate objects in a collection which conforms to the … Read more
