Overloading ++ for both pre and post increment

Can we overload operator++ for pre-increment and post-increment? i.e. calling SampleObject++ and ++SampleObject gives the correct results. class CSample { public: int m_iValue; // just to directly fetch inside main() CSample() : m_iValue(0) {} CSample(int val) : m_iValue(val) {} // Overloading ++ for Pre-Increment int /*CSample& */ operator++() { // can also adopt to return … Read more

Creating methods with infinite parameters?

In C# you can do this: foo = string.Format(“{0} {1} {2} {3} …”, “aa”, “bb”, “cc” …); This method Format() accepts infinite parameters, being the first one how the string should be formatted and the rest are values to be put in the string. Today I’ve come to a situation where I had to get … Read more

Groovy different results on using equals() and == on a GStringImpl

According to the Groovy docs, the == is just a “clever” equals() as it also takes care of avoiding NullPointerException: Java’s == is actually Groovy’s is() method, and Groovy’s == is a clever equals()! […] But to do the usual equals() comparison, you should prefer Groovy’s ==, as it also takes care of avoiding NullPointerException, … Read more

Transfer NULL to the constructor

I can not understand why the constructor is executed with the parameter Double[]? using System.Collections.Generic; using System.Linq; using System.Text; namespace MyConsoleApp { class Program { static void Main(string[] args) { D myD = new D(null); Console.ReadLine(); } } public class D { public D(object o) { Console.WriteLine(“Object”); } public D(double[] array) { Console.WriteLine(“Array”); } public … Read more

Why is const required for ‘operator>’ but not for ‘operator<'?

Consider this piece of code: #include <iostream> #include <vector> #include <algorithm> #include <functional> using namespace std; struct MyStruct { int key; std::string stringValue; MyStruct(int k, const std::string& s) : key(k), stringValue(s) {} bool operator < (const MyStruct& other) { return (key < other.key); } }; int main() { std::vector < MyStruct > vec; vec.push_back(MyStruct(2, “is”)); … Read more

Can I use ‘ == ‘ to compare two vectors. I tried it and seems to be working fine. But I don’t know whether it will work in more complex situations

First example: int main(){ using namespace std; vector<int> v1{10, 20, 30, 40, 50}; vector<int> v2{10, 20, 30, 40, 50}; if(v1==v2) cout<<“equal”; else cout<<“unequal”; } // it returns equal Second example: int main(){ using namespace std; vector<int> v1{10, 20, 30, 40, 50}; vector<int> v2{10, 20, 100000, 40, 50}; if(v1==v2) cout<<“equal”; else cout<<“unequal”; } // it returns … Read more

GCC can’t differentiate between operator++() and operator++(int)

template <typename CRTP> struct Pre { CRTP & operator++(); }; template <typename CRTP> struct Post { CRTP operator++(int); }; struct Derived : Pre<Derived> , Post<Derived> {}; int main() { Derived d; d++; ++d; } I get these errors from GCC: <source>: In function ‘int main()’: <source>:18:10: error: request for member ‘operator++’ is ambiguous d++; ^~ … Read more

Function overloading in Python: Missing [closed]

It’s difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 12 years ago. As function overloading says: Function overloading is absent … Read more

Why does the compiler prefer an int overload to a varargs char overload for a char?

Code public class TestOverload { public TestOverload(int i){System.out.println(“Int”);} public TestOverload(char… c){System.out.println(“char”);} public static void main(String[] args) { new TestOverload(‘a’); new TestOverload(65); } } Output Int Int Is it expected behaviour? If so, then why? I am expecting: char, Int Note: I am using Java 8 Answer Methods with varargs (…) have the lowest priority when … Read more