No – but technically there is a work-around (not that i’d actually use it unless forced to): for(struct { int a; char b; } s = { 0, ‘a’ } ; s.a < 5 ; ++s.a) { std::cout << s.a << ” ” << s.b << std::endl; }
They most often come from forgetting to include the header file that contains the function declaration, for example, this program will give an ‘undeclared identifier’ error: Missing header int main() { std::cout << “Hello world!” << std::endl; return 0; } To fix it, we must include the header: #include <iostream> int main() { std::cout << … Read more
No, there’s no RAM benefit or anything like that. What w3schools is talking about is something I call The Horror of Implicit Globals. Consider this function: function foo() { var variable1, variable2; variable1 = 5; varaible2 = 6; return variable1 + variable2; } Seems simple enough, but it returns NaN, not 11, because of the … Read more
assignment: throwing away the old value of a variable and replacing it with a new one initialization: it’s a special kind of assignment: the first. Before initialization objects have null value and primitive types have default values such as 0 or false. Can be done in conjunction with declaration. declaration: a declaration states the type … Read more
The first way is easier to maintain. Each declaration is a single statement on a single line, so you can easily add, remove, and reorder the declarations. With the second way, it is annoying to remove the first or last declaration because they start from the var keyword and finish with the semicolon respectively. Every … Read more
volatile tells the compiler not to optimize anything that has to do with the volatile variable. There are at least three common reasons to use it, all involving situations where the value of the variable can change without action from the visible code: When you interface with hardware that changes the value itself; when there’s … Read more
4, 5, and 6 are the same thing, only test is a pointer. If you want two pointers, you should use: int *test, *test2; Or, even better (to make everything clear): int* test; int* test2;
As the others have said, you can use var at global scope (outside of all functions and modules) to declare a global variable: <script> var yourGlobalVariable; function foo() { // … } </script> (Note that that’s only true at global scope. If that code were in a module — <script type=”module”>…</script> — it wouldn’t be at global … Read more
There is a difference, but there is no difference in that example. Using the more verbose method: new Array() does have one extra option in the parameters: if you pass a number to the constructor, you will get an array of that length: x = new Array(5); alert(x.length); // 5 To illustrate the different ways … Read more
When you add the const keyword to a method the this pointer will essentially become a pointer to const object, and you cannot therefore change any member data. (Unless you use mutable, more on that later). The const keyword is part of the functions signature which means that you can implement two similar methods, one … Read more