C++ :: Extra Parameter Passing To Overloaded Binary Operator Function
Jun 11, 2013
I have a class matrixType that has some overloaded operators (+, -, *, and <<). With a view to having clearly-delineated, perfectly-formatted, four-sided matrices, as shown below:
A = 1 2 3
4 5 6
7 8 9
or
A + B = 1 2 3
4 5 6
7 8 9
and NOT this jagged ones shown below:
A = 1 2 3
4 5 6
7 8 9
or
A + B = 1 2 3
4 5 6
7 8 9
,
I want a scheme in which the string literals (A, A+B, etc.) could be passed as parameters to the overloaded stream insertion (<<) operator function so that I could use the string’s length to determine how much offset from the display screen’s left to apply to each matrix’s row (by using the setw() function). However, I do know that the << operator is a binary operator, meaning the function cannot take more than two parameters: that is what compounds my problem!
I have a class and I would like to be able to pass an extra parameter to the function that is executed.
BigInt operator / (BigInt N,BigInt D) { ... }
is what I have now. but I would like to do something like this. so the default value for a is 10. and if the user does something like N/D (12) Then the value of a is 12.
why can't << operator be overloaded as a member function is it because that is the way c++ is written and you just can't or is there another reason because I'm confused.
Write a program that inputs 10 integers from the console into an array, and removes the duplicate array elements and prints the array. By removing, I mean that you should make it appear as if the elements hadn't been there. You may assume that all the integers are between 0 and 100, Write at least 1 function in addition to the main function, and pass an array into that function as a parameter. e.g.
Please enter your 10 numbers: 1 2 3 4 5 6 7 8 9 10 The array contains: 1 2 3 4 5 6 7 8 9 10
Please enter your 10 numbers: 1 1 3 3 3 6 7 8 9 9 The array contains: 1 3 6 7 8 9
Please enter your 10 numbers: 1 1 1 1 1 1 1 1 1 1 The array contains: 1
The bolded area is where I'm having trouble. How I can go about doing this, passing an array into the function as a parameter?
Here is my code:
#include "stdafx.h" #include <iostream> using namespace std; int main () { const int MAX = 10; int a[MAX] = {0}; int i;
Pseudocode: template<typename T /*, some parameter for member_function */> class Foo { public: void someFunction() { T t; t.member_fuction(...); } }
I'm trying to make the call to T::member_function a templated value because member_function might vary by name in my scenario. Since std::mem_fn isn't a 'type', i can't do something like Foo<std::string, std::mem_fn(&std::string::clear)> foo;
I also want to take into account that member_function might have more than one parameter. That is, the first parameter will always be something known but there might be other defaulted parameters.
The only thing I can think of is to make a proxy structure, something like this:
I created the following code to pass the the variable 'inputVoltage' by reference to the function 'input'. It certainly works when I run the program, but I dont think it is a standard way of doing it, i.e. the use of '*' and '&' is not according to convention ? Or perhaps the way did it is acceptable ?
int input (double *inputVoltage); int main ( { double inputVoltage; input(&inputVoltage);
While running it gives the runtime error: "Extra parameter in call to factorial."
#include<iostream.h> #include<conio.h> int factorial(long int); void main() { clrscr(); long int a; cout<<"This program displays the factorial of the number you enter."<<endl;
Basically I'm trying to pass an object as a reference to the template function, rather than a copy as it's seeing. I'm needing to do this without editing Obj::Call to accommodate a reference as its first parameter, as it'd break other calls.
You'll notice in the following code the object will be destroyed upon passing, while the object defined is still in-scope due to the infinite end loop.
#include <iostream> #include <string> using namespace std; class Obj { public: string name; Obj(string name): name(name) {cout << "create " << this << endl;}
[code]....
In the past I tried ref(), which appeared to stop this happening, however it created a blank copy of the object instead.
The thing is, when I don't create a prototype of count and straightaway define it before void main() my program runs, but it gives error in this program that "extra parameter in call to count()" But what to do then?
I have two possible questions; can you use a ternary operator to initialize objects with overloaded constructors like
class thing { int x; int y;
[Code].....
I can get around it if I need to but I'd like to learn more about the ternary operator if I can, since I couldn't find anything online that addressed this particular issue, at least in a way I could detect.
I'm using some overloaded operators (addition, subtraction and variants of) in part of my final major project and, when coming to test it, I've noted that they appear to be killing my pointers eventually.
I say pointers, it's always the same one. But I have isolated it to being the operators. The only two I'm really using are += and -=, though I've defined the others for consistency.
Either A ) what it is I've done wrong (if I have) or B ) why I would see this behaviour. Or, you know, if there's something glaringly obviously wrong with the code that I'm glossing over.
Code is as follows
#pragma once #include "stdafx.h" namespace gunpei { /** A paired register in the form of r1r2 Enables using two separate arrays for register processing provides logic for assembling pair and breaking back into individual registers */ class GBPairedRegister {
Is it possible with a struct? How to express this to search engines so I haven't been able to find anything about it. If this is not possible with a struct, is there a way to define something that can do all the following things:
SomeStruct test = {0.5, 0.5, 0.5, 1}; test.g = 1.0; test[0] = 0.0; // test[0] would be equivalent to calling test.r float somevalue = test[3]; // test[3] would be equivalent to calling test.a
I designed a class template to create unique arrays. I was able to successfully input data to and output data from my array objects, irrespective of the datatype. However, I can't for the life of me fathom why my overloaded assignment operator worked perfectly well only for integer datatype and not for double/string datatypes.
Here is the class definition:
template <class dataType> class myArray { public: void setArrayData();
[code]....
And here is the definition of the overloaded assignment operator:
And here is my main function that tests the operations on objects of the class:
int main(){ //object declarations myArray<double> list(5); //a single-parameter object declaration of class myArray myArray<double> myList(2,13); //a two-parameter object declaration of class myArray
[code]....
The problem I'm having starts from where the assignment operator is being tested: for double and string datatypes, the upper input/output section works fine, but the assignment section freezes the display until the program execution is manually terminated!
I create two memory manager called CMemManager1 and CMemMangaer2, using different algorithms to allocate buffer. Now I want to control which memory manager to be used, when calling new.
I try to add a parameter bUseWhichMemManager to the constructor, but in overrided new function, there are no way to access the parameter. Is there a way to pass more parameters to new operator, such as:
My errors are at the end of the program in two function calls within the definition of the InsertByValue function. g++ does not seem to recognize NumArray as a valid parameter.
#include <iostream> #include <assert.h> using namespace std; const int CAPACITY = 20;
/* Displays the content of an int array, both the array and the size of array will be passed as parameters to the function @param array: gives the array to be displayed @param array_size: gives the number of elements in the array */ void DisplayArray (int array[], int array_size);
In a .h file there is a function that takes in this parameter:
void (^callback)(float * arg)=NULL
as in a function definition:
void func(void (^callback)(float * arg)=NULL);
What I am able to read is that it takes a function pointer and if not defined it overrides with NULL. The part I do not get is the ^ in (^callback). I only know ^ as a bitwise XOR operator. It also generates issues in my VS2012 compiler (something with CLR). So I would really like to rewrite this part to something else, without the bitwise operator...
#include <cstdlib> #include <iostream> struct tax_node { char form; // tax form letter int version; // tax form number
[Code] ....
I cannot seem to get why function print_contents will not work. The couts at the end of the program is just to test that it printed correctly. But, if I need it to print the contents such when print_contents(ptr2) is called. I think it should be tax_ptr in the parameter list but I am not quite sure.
I want to create events and then, functions which are subscribed to the event can access information about the event. For example, in Class 2 below, I want it to be able to access things such as touch.position, etc. of class 1.
Class 1:
public delegate void TouchEventHandler (EventArgs e); public event TouchEventHandler TouchBegan; public Vector2 touchPosition; void Update () { if (Input.touchCount > 0) {
But when I try to build it, I get this error on line 24:could not convert template argument 'lambda' to 'void (*)(const string&) {aka void (*)(const std::basic_string<char>&)}'|
I thought the lambda expression I wrote would decay to a function pointer matching the template parameter. I can guess that the constexpr qualifier might have changed the type, but without it my compiler complains that lambda needs to be declared as constexpr...
So is there a way to pass lambda expressions as template parameters?