Comments on: 9.1 — Introduction to operator overloading http://www.learncpp.com/cpp-tutorial/91-introduction-to-operator-overloading/ Wed, 20 Aug 2008 09:34:33 +0000 http://wordpress.org/?v=2.5.1 By: Learn C++ - » 8.14 — Anonymous variables and objects http://www.learncpp.com/cpp-tutorial/91-introduction-to-operator-overloading/#comment-14400 Learn C++ - » 8.14 — Anonymous variables and objects Mon, 05 May 2008 02:01:03 +0000 http://www.learncpp.com/cpp-tutorial/91-operator-overloading/#comment-14400 [...] 9.1 — Introduction to operator overloading [...] [...] 9.1 — Introduction to operator overloading [...]

]]> By: ethicalstar http://www.learncpp.com/cpp-tutorial/91-introduction-to-operator-overloading/#comment-11204 ethicalstar Tue, 08 Apr 2008 09:37:59 +0000 http://www.learncpp.com/cpp-tutorial/91-operator-overloading/#comment-11204 ofcourse! rightly said!!! ofcourse! rightly said!!!

]]> By: Alex http://www.learncpp.com/cpp-tutorial/91-introduction-to-operator-overloading/#comment-6081 Alex Tue, 15 Jan 2008 20:30:46 +0000 http://www.learncpp.com/cpp-tutorial/91-operator-overloading/#comment-6081 Consider the following mathematical equation: 5 * 2 ^ 3 Using standard mathematical precedence rules, exponents are evaluated before multiplication. Thus, we'd solve this equation as: 5 * (2 ^ 3), which evaluates to 5 * 8 = 40. Now, let's say we overloaded the XOR operator (^) to make it do exponents instead of bitwise XOR. According to C++ precedence rules, the multiplication operator takes precedence over the XOR operator. As a result, C++ would evaluate our mathematical equation above like this: (5 * 2) ^ 3. Consequently, it would produce the result 1000 instead of 40. This would be unintuitive to someone expecting the equation to be evaluated according to normal mathematical precedence rules. Thus, it would not be a good idea to overload the XOR operator in this way. Unfortunately, there is no way to change the precedence of operators in C++. Consider the following mathematical equation: 5 * 2 ^ 3

Using standard mathematical precedence rules, exponents are evaluated before multiplication. Thus, we’d solve this equation as: 5 * (2 ^ 3), which evaluates to 5 * 8 = 40.

Now, let’s say we overloaded the XOR operator (^) to make it do exponents instead of bitwise XOR. According to C++ precedence rules, the multiplication operator takes precedence over the XOR operator.
As a result, C++ would evaluate our mathematical equation above like this: (5 * 2) ^ 3. Consequently, it would produce the result 1000 instead of 40. This would be unintuitive to someone expecting the equation to be evaluated according to normal mathematical precedence rules. Thus, it would not be a good idea to overload the XOR operator in this way.

Unfortunately, there is no way to change the precedence of operators in C++.

]]> By: Renu http://www.learncpp.com/cpp-tutorial/91-introduction-to-operator-overloading/#comment-6079 Renu Tue, 15 Jan 2008 19:37:02 +0000 http://www.learncpp.com/cpp-tutorial/91-operator-overloading/#comment-6079 I didnt understand this "all operators keep their current precedence and associativity, regardless of what they're used for. For example, the bitwise XOR operator (^) could be overloaded to do exponents, except it has the wrong precedence and associativity and there is no way to change this " Could you please elaborate this? Thanks, Renu I didnt understand this
“all operators keep their current precedence and associativity, regardless of what they’re used for. For example, the bitwise XOR operator (^) could be overloaded to do exponents, except it has the wrong precedence and associativity and there is no way to change this ”

Could you please elaborate this?
Thanks,
Renu

]]> By: Alex http://www.learncpp.com/cpp-tutorial/91-introduction-to-operator-overloading/#comment-6015 Alex Mon, 14 Jan 2008 16:01:03 +0000 http://www.learncpp.com/cpp-tutorial/91-operator-overloading/#comment-6015 The people who write compilers are very smart! :) The people who write compilers are very smart! :)

]]> By: Abhishek http://www.learncpp.com/cpp-tutorial/91-introduction-to-operator-overloading/#comment-6006 Abhishek Mon, 14 Jan 2008 13:07:08 +0000 http://www.learncpp.com/cpp-tutorial/91-operator-overloading/#comment-6006 compilers are very smart! compilers are very smart!

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