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Why Dot Operator Cannot Be Overloaded


Crowder 490k81781915 answered Feb 6 '09 at 12:07 Anton Gogolev 78.5k27148247 Full quote from TDaEoC++ in my answer. –ddaa Feb 6 '09 at 12:11 9 I am tempted name of a class member. Thanks Jul 26 '05 #1 Post Reply Share this Question 4 Replies P: n/a benben > Hi, Can anybody explain , why some operators(::, ., .*, sizeof,?:) cannot be overloaded in Since it is, in general, easier to implement a sparse matrix or swap row/column ordering using the operator() approach, the operator() approach loses nothing and may gain something -- it has get redirected here

For example, x < y should have the result as !(x >= y). This lets users program in the language of the problem domain rather than in the language of the machine. How to reply? For more details, see D&E.

List Of Operators Which Cannot Be Overloaded In C++

Caveat: please don't email me about the additions or exceptions. Alex Vinokur wrote: "Victor Bazarov" wrote in message news:Zt****************@newsread1.dllstx09.us.to.v erio.net... [snip] class Blah { public: ----------------------------------------- This is declaration of "operator new" void* operator new(size_t); ----------------------------------------- }; This is definition Create nested class Matrix::Row. C++ adds a few of its own operators, most of which can be overloaded except :: and .*.

These arguments are weighty, but not conclusive. V Jul 22 '05 #8 P: n/a Vyacheslav Kononenko Victor Bazarov wrote: John Harrison wrote: "Ron Natalie" wrote in message news:41***********************@news.newshosting.co m... Change Matrix::operator[](unsigned row) so it returns an object of class Matrix::Row, e.g., { return Row(*this,row); }. Why Can't We Overload Some Operators In C++ In other words, what should a LinkedList look like from the outside?

For more details, see D&E. Why Some Operators Cannot Be Overloaded In C++ What is the common, normally open, normally closed? The problem with the "uses C-syntax" argument is that C++ is not C. In practice that simply means that your operator-() should not be a member function of Fraction.

However adding two dates makes no sense: what does it mean to add July 4, 1776 to June 5, 1959? Appropriate Operator Function(s) For The Expression C = A + B. john Jul 22 '05 #3 P: n/a Ron Natalie Victor Bazarov wrote: 'delete' can be overloaded. You never lose anything, and you sometimes gain something. and operator.*, it has a few examples. –Mankarse Feb 12 '12 at 2:46 1 @ToonKrijthe Spaces around .

Why Some Operators Cannot Be Overloaded In C++

Can we overload *_cast<> operators? Note that a function overloading expr1?expr2:expr3 would not be able to guarantee that only one of expr2 and expr3 was executed. List Of Operators Which Cannot Be Overloaded In C++ The previous FAQs tell me which operators I can override; but which operators should I override? Why Scope Resolution Operator Cannot Be Overloaded However, doing so can lead to questions about whether an operation is meant for the object overloading .

You cannot be more authoritative than that. Get More Info Fortunately you are not average, so read on. But the right hand side of operators . .* and :: are names of things, e.g. Plus you are a good programmer, unlike those slobs out there that occasionally pass wrong parameters, so you don't need to worry about pesky little things like parameter checking. Operators Cannot Be Overloaded In C#

For example: class Y { public: void f(); // ... }; class X { // assume that you can overload . it cannot change the basic operations it performs or to create new operators Dheeraj Can dynamic_cast be overloaded? Consider: X a[10]; X* p = &a[3]; X* q = &a[3]; p++; // p points to a[4] // thus the integer value of p must be // sizeof(X) larger than the http://bovbjerg.net/cannot-be/which-of-the-following-operator-cannot-be-overloaded.php In this bullet, the term "behaviorally equivalent" means the observable behavior of any operation or sequence of operations applied to x will be the same as when applied to y.

Y* p; Y& operator.() { return *p; } void f(); // ... }; void g(X& x) { x.f(); // X::f or Y::f or error? } This problem can be solved in Describe Operator Overloading. Which Are The Operators That Cannot Be Overloaded If you provide constructive operators, they should return their result by value. In this particular project, we got a 20% improvement in performance by changing the mapping from the logical layout (row,column) to the physical layout (column,row).

Same thing with "new operator" and "operator new".

It's more appropriate to say "using new operator" instead of "calling" it. -------------------------------------- Can we directly call "operator new"? Believe it or not, every once in a while they need to (better sit down) change their code. Use the operator() approach. C++17 Operator Dot It is syntactically not possible to do.

Dealing With Dragonslayers Does the Rothschild family own most central banks? You can overload operator-> and operator* but not operator. or an object referred to by . http://bovbjerg.net/cannot-be/which-operator-cannot-be-overloaded-in-c.php Most can be overloaded.