When compiling the code
#include "tensor.h"
int main() {
Tensor<2,-2> m = {{1,2},{1,3}};
Tensor<2> v = {1,5};
std::cout<<m*v<<"
[Code] ....
Why do I get an ambiguity and why is not the wanted operator*-overload (the last one in the tensor.h file) not even mentioned as one of the candidates? Is it clear what I want to do? And if so, what can I do to make the call unambiguous?
I get the following error in XCode whenever I try to access the member I created 'randomGen' in a separate class in a different header file. I have made sure to include the header file and have tried to access it through an object.
This is the code I enter when trying to access the method from randomiser.h in main.cpp. It is also an overloaded function with doubles and integers:
RandomG randomiser;
randomiser.randomGen(); // 'Call to member function 'randomGen' is ambiguous'
This is the code inside randomiser.h:
#include <string>
#include <iostream>
using std::string;
using std::cout;
using std::endl;
class RandomG {
[Code] ....
This is the error inside xcode: [URL] ....
I have tried seperating the code for the functions in another class (main.cpp) and then running and it seems to works, so I'm not sure why I can't put everything in the .h file and then access it?
I would like it in a seperate file so it doesn't clutter my main. I am writing a game with SDL so that might be confusing and I would like the window to have a random title and other random properties, so it would be easier to use a function.
Code:
void write() {
setlocale(LC_ALL, "en_US.UTF-8");
cout <<"";
}
template <typename A, typename ...B>
void write(string argHead, B... argTail) {
setlocale(LC_ALL, "en_US.UTF-8");
[Code] ....
what I'm doing wrong with my write() function? I did like the read() function(for work diferent with another types) but i get these error:
"C:UsersJoaquimDocumentsCodeBlocksMy Classconsole.h|218|error: call of overloaded 'to_string(char*&)' is ambiguous|"
What I'm trying to do is create a class for constructing an 'op tree' for parsing infix notation.
I started with a base class that uses a map of lambdas to actually calculate the operations (since they are mostly 1 line functions) of passed in integer or float values.
This base class just uses a templated T type as the lvalue and rvalue. I realized though that if I overload the math operators, +, -, etc.. I could also use the class itself as a type for the lvalue and rvalue. This lead me to think I could easily create the op tree by using Operation class members themselves as operands, which I think makes sense but I'm having some trouble expressing the code.
Heres what I have thus far
Code:
#include <map>
#include <string>
#include <algorithm>
#include <iostream>
namespace Calc {
[Code] .....
Example, if you look at the main() function I create normal operations easily with integer values. I then try to create a "tree" operation that includes 2 sub-operations as it's rvalue and lvalue, that is where I'm having some conceptual problems as far as implementing the code to do that.
I'm having an issue with output, luckily everything else works!! I'm working with Mixed Numbers and operations on them. So, here's the code I'm testing with:
int main() {
Mixed m1(5), m2(1,1,1), m5(2,2,3);
cout << "m1+m2= " << m1+m2 << endl;
cout << "m1 + 10=" << m1+10 << endl;
cout << "m1 - 10=" << m1-10 << endl;
return 0;
}
And here is the output for that code:
File name: fract.h
#ifndef fract_H
#define fract_H
#include <iostream>
using namespace std;
const int DEFAULT_VAL = 0;
[Code] ....
I believe I have the syntax correct but I'm having difficulty calling my overloaded == operator in main (last snip-it of code). Below are several files explaining the code.
Commission.h here is where the friend bool operator == exists and I believe I have it initialized correctly.
#ifndef COMMISSION_H_INCLUDED
#define COMMISSION_H_INCLUDED
using namespace std;
class Commission {
public:
Commission();
Commission(int, double, double, double );
~Commission();
[Code] .....
I need to make a stub for some standard library function, but the compiler gets confused about which function I want to call in my code. I thought that putting the stubbed function together with its caller into an anonymous namespace will give higher precedence to the stub, but it didn't.
Here is an example code:
#include <cstdlib>
#include <cstdio>
#include <cstring>
#include <signal.h>
namespace{
int sigaction(int signum, const struct sigaction * act, struct sigaction * oldact)
[Code] ....
Result:
main.cpp: In function ‘void {anonymous}::test()’:
main.cpp:23:47: error: call of overloaded ‘sigaction(int, sigaction*, NULL)’ is ambiguous
main.cpp:23:47: note: candidates are:
main.cpp:8:5: note: int {anonymous}::sigaction(int, const sigaction*, sigaction*)
In file included from main.cpp:4:0:
/usr/include/signal.h:266:12: note: int sigaction(int, const sigaction*, sigaction*)
It possible to force the compiler to use my stubbed version of sigaction() and if yes, how to do that? I am not allowed to modify test() function.
I am working on a school project and am stuck in the debugging. I am compiling with g++ and am using c++11.
Error message
In file included from /usr/include/c++/4.7/algorithm:63:0,
from date.h:7,
from date.cpp:1,
from schedule.h:1,
from schedule.cpp:1,
from date_driver.cpp:1:
[Code] ....
Here are my overloaded operators for my date class.
bool Date :: operator == (Date otherDate){
if (((otherDate.getDay () == getDay ()) && (otherDate.getMonth () == getMonth ())) && (otherDate.getYear () == getYear ()))
[Code] .....
I'm implementing a rational number class:
#include <iostream>
#include <stdint.h>
using namespace std;
typedef int64_t RAT_INT;
struct RAT{
RAT_INT Num, Den;
RAT(RAT_INT num = 0, RAT_INT den = 1){
Num = num;
Den = den;
[Code].....
Two questions:
1) In the second line in main, how does C++ know to convert 2 to the appropriate RAT?
2) Is it possible to make the third line in main valid without adding global operators for all the member operators to support plain integers?
This code is meant to open a file and use overloaded operators for a complex number class. I am getting a lot of errors in my class declaration/definition but I am not sure why.
#include <iostream>
#include <cmath>
#include <fstream>
class CN {
public:
double real;
double im;
[Code] ....
I had to learn how to use variadic templates recently, and had trouble finding simple examples that just showed the basic syntax.
So I decided to write one myself. Admittedly, it's a bit on the long side, but that is mostly because it includes five specializations.
insert Code:
// Variadic.C
// Compile command: g++ Variadic.C -std=c++0x
// I used GCC version 4.6.3 on Ubuntu.
// This file contains a basic variadic template with five specializations.
// It is intended for non-software engineers who are looking for a simple
// example of variadic template syntax.
[Code] ....
I wonder if it is possible to remove the last argument in an argument pack? Below is an example on what I want to accomplish:
template<template<int...> class A,int... Ints>
A<remove_last_int<Ints...>::list> func(const A<Ints...> & a0)
{
A<remove_last_int<Ints...>::list> a;
...
//Here a set the members of a based on a0.
...
return a;
}
For example, I want the return a A<1,2> value from (const A<1,2,3> & a0)
template <typename FIRST, typename... REST, typename std::enable_if<std::is_convertible<FIRST, Base*>::value>::type* = nullptr>
void foo (FIRST first, REST... rest) {}
that successfully allows me to enable the function foo() only if FIRST is convertible to Base*, but I also only want foo() enabled if each type in REST... meets the same condition. What is the syntax for that? If no such syntax exists, how to achieve that effect?
I'm having some problems in understanding how the code below works and why it produces the output it produces.. What I'd expect is that both functions, namely `add_1' and `add_2', would print the same output; but I've been proven wrong :/ So why does the second one get different memory addresses for the same variable?
Code should be self-explaining:
Code: template<typename... Types>
void add_1(Types&&... values)
{
// by the way: why do i have to use `const int' instead of `int'?
std::vector<std::reference_wrapper<const int>> vector{
std::forward<Types>(values)...};
std::cout << "add_1:" << std::endl;
for (const auto& value:vector) {
std::cout << &value.get() << std::endl;
[code].....
I'm trying to expand a template + argument parameter list inside a lambda function like this:
template <typename Class, typename ...Args>
static void create(Args ...args) {
// Perform pre-thread creation work.
std::thread([=]()
[Code] ....
But this does not work:
The compiler error is "error: parameter packs not expanded with ‘...’:|"
However, when I do the following:
template <typename Class, typename ...Args>
static void create(Args ...args) {
// Pre-thread work.
auto tthr = [](Args ...ar) -> void {
[Code] ....
It works just fine. That shows that lambda threads are able to take variadic arguments...
So here is my question; what is the correct capture clause for capturing the variadic object correctly?
I have been experimenting with variadic templates with the aim of caching a call to a class method by storing away the object pointer, method pointer and parameters. I've actually had some reasonable success but have now hit a stumbling block. I now wish to wrap my parameters in a simple template class when I cache them. My success is as follows:
Using variadic template functions to store these pointers and paremeters;
I'm able to pass a method pointer and unwrapped parametersI'm able to pass wrapped parameters on their own.I'm NOT able to pass a method pointer and wrapped parameters I set up a little prototype project to demonstrate the issue and added comments above the function calls to indicate the compilation results. Here is the code:
Code:
#include "stdafx.h"
//////////////////////////////////////////////////
// Basic class with a simple method
//////////////////////////////////////////////////
class MyClass {
public:
char Method( int i, float f ) {
return 'A';
[code]....
But I'm convinced it should take three arguments, the method pointer and two wrapped parameters. Visual studio even suggested it should as shown below:
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:
template<class dataType>
const myArray<dataType>& myArray<dataType>::operator=(const myArray<dataType>& rightArray) {
int i;
if(this != &rightArray) {
delete [] arrayPtr;
[Code] ....
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!
The code below doesn't compile. Two things to clear up:
1) I know x is going to be garbage.
2) I used the same type name label ElementType.
#include <iostream>
#include <ostream>
template <typename ElementType>
class Example {
[Code] .....
I have a .cpp file which I have to create a header file for. I started it but I have stuck and it is full of errors.
I have some tasks (see comments in the code):
Task 2: I have to write a template which defines min max operators on vectors, it must be a custom vector template. The main program only demonstrates that it creates a data structure which calls for min max operators.
Task 3: I need a special min max function which watches for any changes and it has to work lineally so it has to step along the elements of the vectors determining the min max values.
Task 4: I have to create an iterator function
Here is the main.cpp code:
Code:
#include <iostream>
#include "mmvec.h"
#include <algorithm>
#include <string>
#include "mmvec.h"
struct Limited {
int val;
[Code] ...
My load function isnt working. I've tested it and returned it as an int and it worked but when i tried to compile when i changed it to a template i started getting the errors and I'm not sure how to fix it:
all_sort.cpp:41:15: error: no matching function for call to 'load'
int *value = load("./integers.txt", size);
^~~~
./bubble_sort.h:44:4: note: candidate template ignored: couldn't infer template
argument 'T'
T *load(const char* x, int &size) {
[Code] ....
I'm trying to use my load function to load integers from a file into and array and then return it back.
#include "bubble_sort.h"
#include <iostream>
#include <cstdlib>
#include <string>
using namespace std;
int main(){
int n, pick = 1, size = 0;
[Code] ....
This week we are learning to use templates, and I don't understand how to call my member functions with my template based class. I tried the standard convention of calling member functions, but I keep getting an error saying name following"::" must be a class or namespace name. I'm thinking my problem lies with my typename T, but I am unsure. Line 16 is where I am getting tripped up.
#include "stdafx.h"
#include <iostream>
#include <string>
using namespace std;
template<class T>
T Set
{
public:
[Code]...
I'm using GCC 4.8.1 and I want to implement a XML parser using TinyXML and port it to AngelScript
Now, it says: reference to 'Column' is ambiguous
I've declared a class called xml_parser and I've added everything of tinyxml as it's public member when I call Column(), and also Row(), it give's this error. what should I do?
This is it's code:
xml_parser.hpp:
#ifndef AGK_XML_PARSER_H
#define AGK_XML_PARSER_H
#define TIXML_USE_STL
#include <tinyxml.h>
[Code] .....
Okay so inside my ArcherArmor.cpp, I'm trying to figure out why the map initializer list isn't working, but for some reason I keep getting "Error C2593: 'operator =' is ambiguous". Here is my code:
I also have a class which ArcherArmor is derived from, that has a struct called `Armor`, which I left out for simplicity. The main problem is that error! The only thing I can think of is that im initializing the map wrong.
//ArcherArmor.h
#include <string>
#include <map>
class ArcherArmor {
private:
map <int, Armor> soldier_armor;
public:
void ArcherArmor_shop();
[Code] .....
Here is the error I am getting:
1>d: estprojectgdiplusrenderer.h(61): error C2872: 'Font' : ambiguous symbol
1> could be 'c:program files (x86)microsoft visual studio 10.0vcincludecomdef.h(312) : Font'
1> or 'c:program files (x86)microsoft sdkswindowsv7.0aincludegdiplusheaders.h(244) : Gdiplus::Font'
How can I fix this issue?
The compiler keeps on telling me that invalid conversion from wxBitmap* to wxString on the line with the AddTool function, whiles I do not even try to do such an ambiguous typecast.
wxWidgets 2.9.4
MinGW
gdb
Code:
#include "mainwnd.h"
//namespaces
//other definitions and declarations
CMAINWND::CMAINWND(const wxString& szTitle):wxFrame(NULL,wxID_ANY,szTitle) {
wxImage::AddHandler(new wxBMPHandler);
[Code] .....
Let's say I have a templated base class:
Code:
template <typename Input>
class Consumer
{
public:
void consume(Input input)
{
// do something
}
};
Now, I have a class which derives from this twice (A and B are unrelated, but otherwise unimportant classes):
Code:
class A;
class B;
class Derived: public Consumer<A>, public Consumer<B>
{
};
Now, elsewhere in the code I do this:
Code:
{
A myA;
Derived myDerived;
myDerived.consume(myA);
}
This looks like it should be simple enough, but g++ 4.8.1 is giving me a "request for member is ambiguous" error.