You are trying to index on the pointer rather than the map itself. Kind of confusing because usually with pointers vs. values dereferencing is automatic for structs. If your struct is just a map, however, it’s only passed in by reference anyway so you don’t have to worry about creating methods that act on pointers … Read more
There is nothing really wrong, but it will certainly limit the use of the template. You won’t be able to just put an iterator returned by something else or generated like v.begin(), since those will be temporaries. You will always first have to make a local copy, which is some kind of boilerplate not really … Read more
Why can’t you use function overloading? Surely it’s the easiest solution to your problem? void foo(double &bar, double &foobar) { bar = 100; foobar = 150; } void foo(double &bar) { double foobar = 0.0; foo(bar, foobar); }
A good way to find out why there are any differences is to check the disassembly. Here are the results I got on my machine with Visual Studio 2012. With optimization flags, both functions generate the same code: 009D1270 57 push edi 009D1271 FF 15 D4 30 9D 00 call dword ptr ds:[9D30D4h] 009D1277 8B … Read more
There isn’t a way to pass a primitive directly by reference in Java. A workaround is to instead pass a reference to an instance of a wrapper class, which then contains the primitive as a member field. Such a wrapper class could be extremely simple to write for yourself: public class IntRef { public int … Read more
Only call time pass-by-reference is removed. So change: call_user_func($func, &$this, &$client … To this: call_user_func($func, $this, $client … &$this should never be needed after PHP4 anyway period. If you absolutely need $client to be passed by reference, update the function ($func) signature instead (function func(&$client) {)
C++/CLI itself doesn’t support a real ‘out’ argument, but you can mark a reference as an out argument to make other languages see it as a real out argument. You can do this for reference types as: void ReturnString([Out] String^% value) { value = “Returned via out parameter”; } // Called as String^ result; ReturnString(result); … Read more
Here is my own contribution for the Java programming language. first some code: public void swap(int x, int y) { int tmp = x; x = y; y = tmp; } calling this method will result in this: int pi = 3; int everything = 42; swap(pi, everything); System.out.println(“pi: ” + pi); System.out.println(“everything: ” + … Read more
Because the array is being passed by value, an exact copy of the array is made and placed on the stack. This is incorrect: the array itself is not being copied, only a copy of the pointer to its address is passed to the callee (placed on the stack). (Regardless of whether you declare the … Read more
Strings in Javascript are already passed “by reference” — calling a procedure with a string does not involve copying the string’s contents. There are two issues at hand: Strings are immutable. In contrast to C++ strings, once a JavaScript string has been created it cannot be modified. In JavaScript, variables are not statically assigned slots … Read more