After performing this test with most modern browsers: https://jsben.ch/wY5fo Currently, the fastest form of loop (and in my opinion the most syntactically obvious). A standard for-loop with length caching var i = 0, len = myArray.length; while (i < len) { // your code i++ } I would say, this is definitely a case where … Read more
You can use an enhanced for loop: Set<String> set = new HashSet<String>(); //populate set for (String s : set) { System.out.println(s); } Or with Java 8: set.forEach(System.out::println);
Oh, I found it. You use last instead of break for my $entry (@array){ if ($string eq “text”){ last; } }
No, but you can provide your own counter. The reason for this is that the for-each loop internally does not have a counter; it is based on the Iterable interface, i.e. it uses an Iterator to loop through the “collection” – which may not be a collection at all, and may in fact be something … Read more
for /l is your friend: for /l %x in (1, 1, 100) do echo %x Starts at 1, steps by one, and finishes at 100. WARNING: Use %% instead of %, if it’s in a batch file, like: for /l %%x in (1, 1, 100) do echo %%x (which is one of the things I … Read more
Which is better, a or b? From a performance perspective, you’d have to measure it. (And in my opinion, if you can measure a difference, the compiler isn’t very good). From a maintenance perspective, b is better. Declare and initialize variables in the same place, in the narrowest scope possible. Don’t leave a gaping hole … Read more
This depends on the language being used. You wrote ‘language-agnostic’, so I’ll give some examples. In Java, C, and Python, recursion is fairly expensive compared to iteration (in general) because it requires the allocation of a new stack frame. In some C compilers, one can use a compiler flag to eliminate this overhead, which transforms … Read more
You can use generator expressions like this: gen = (x for x in xyz if x not in a) for x in gen: print(x)
Use next: (1..10).each do |a| next if a.even? puts a end prints: 1 3 5 7 9 For additional coolness check out also redo and retry. Works also for friends like times, upto, downto, each_with_index, select, map and other iterators (and more generally blocks). For more info see http://ruby-doc.org/docs/ProgrammingRuby/html/tut_expressions.html#UL.
Try range(100,-1,-1), the 3rd argument being the increment to use (documented here). (“range” options, start, stop, step are documented here)