C++ :: Implementation File Versus Header File - Eclipse Giving Errors
Feb 10, 2013
I have written my program and it works when I keep everything in the header files, and then have my main. I am now splitting them up into implementation files, but Eclipse keeps giving me errors. It gives me error at every opening brace of the constructor and functions. It says on all of them "Redefinition of (name of constructor or method), Previously declared here." What am I doing wrong, because it works in the header file?
I am trying to separate out particular sets of routines into a separate implentation and header file which can be compiled independently to the main program such that the program source consists of a file called customers.h, customers.cpp, and exercise_1_5.cpp
Each of the files should contain the following:
customers.h should contain the definition of the customer structure and the declaration of print_customers.
customers.cpp should contain the implementation (or definition) for print_customers.
exercise_1_5.cpp should contain an include of customers.h and the main program.
This is my original code from a single .cpp file
#include<iostream> #include<string> using namespace std;
[Code].....
The error messages I am getting from the compiler on the customers.cpp file:
C:UsersBenDocumentsCS264lab3customers.cpp:5:22: error: variable or field 'print_customers' declared void C:UsersBenDocumentsCS264lab3customers.cpp:5:22: error: 'customer' was not declared in this scope C:UsersBenDocumentsCS264lab3customers.cpp:5:32: error: 'head' was not declared in this scope
I'm using Code:Blocks 12.11 on windows 7, with the built-in MinGW compiler. When I try and compile a program that has an error in it (misnamed variable, missing include, extra semi-colon somewhere, anything) instead of saying something about what went wrong it just has this:
Process terminated with status 1 (0 minutes, 0 seconds) 0 errors, 0 warnings (0 minutes, 0 seconds)
I've implemented the merge sort algorithm and used the 'merge' part for counting the number of split-inversions in an array as part of an assignment for an online course. How ever, the out put array is not a sorted version of the input array and as a result the number of split inversions obtained is wrong. I think that there is some thing wrong in the way I am indexing arrays.
I've used ' cout ' to print the values of indexes to see exactly what values are being passed in during the recursions.
Code:
#include <iostream> using namespace std; int length=0,mid=0,inv=0; void mergesort(int arr[], int first, int last) { cout << "first: " << first << " " << "last: " << last; cout << endl;
I'm making a game with the following class structure:
GameControl - The class that actually runs the game, with a while(!closed) // run the game loop.
State - A class that handles the state of the game, for example if the game is rendering the scene it would be in one state, and if it is rendering the menu, it would be in another.
ComponentManager - A class that manages all of the components of what is being done, for instance, the Scene class would contain a bunch of components handling the drawing of each tree, physics, the camera, etc. The manager will put them all together.
Component - A component of whatever is being done. A tree (and its rendering code) would be an example of a component of the scene. The camera would be another. The component does not necessarily have to be drawn, it could be handling something like physics (and would throw physics events to other components that need to move in a certain way).
The GameControl class has its loop, which would call the update function on the current State (there are classes that inherit State and override the update function of State).
In the update function of the base class "State", it would take all of the active ComponentManagers and update them. There are classes that inherit the base class ComponentManager and override its update function.
Each ComponentManager would update each of the Components that it owns.
This is the organizational structure that I came up with to make the game scalable and changeable . If, for instance, I wanted to add multiplayer at some point, I would add a class that inherits the State that controls the gameplay called "MultiplayerGameState". This would just add a new ComponentManager that inherits the ComponentManager that controls the player and all of the living things that are moving around. Then, the MultiplayerGameState class would recieve the multiplayer messages coming in and add other player Components for the other players.
My code is giving me various errors like "Forward definition of class State" and "Invalid use of incomplete type State". Unless I made some stupid error that I didn't catch, these are being caused by me including the classes in ways that some of the classes do not see the full definitions of the classes they need to see (because of the preprocessor directives preventing classes from being included multiple times.
Code: (Not implemented exactly as shown above, but I think the main difference is that the main class is not in GameControl, it's in OgreFramework.cpp)
The base classes: [URL] ... States: [URL] ... ComponentManagers: [URL] ... Components: [URL] ... The project: [URL] ...
My question is: is there a better way to implement my organizational system so that these errors don't occur?
I just re-installed my OS some days ago,which contained Visual Studio.But I don't want to use the VS any more(at least in my computer) as the interminable installing process.Then I take Eclipse as my C/C++ IDE by MinGW and CDT. My Java program need to load an DLL file which wrote by C.But when I generating the DLL file,I got some errors.It seems that the compiler cannot find the header files. By the way,I just want to implement the hello-world program in C and invoke it in the Java program.This is my Java testing program:
Code:
public class HelloWorld{ public native void printHelloWorld(); static{ System.loadLibrary("hello"); } public static void main(String[] args){ new HelloWorld().printHelloWorld(); } }
And this is the header file generating by "javah HelloWorld":
Code:
/* DO NOT EDIT THIS FILE - it is machine generated */#include <jni.h>/* Header for class HelloWorld */ #ifndef _Included_HelloWorld #define _Included_HelloWorld #ifdef __cplusplus extern "C" { #endif
I'm creating a bank system. So I know to make a deposit to the balance, which add ups what is the balance to i have add.
When i run the deposit function, its work well in some ways. If balance(text file) has the value 10, add i addSum 20, the balance will become 30, same as the text file will become 30. so its work well to add positive number.
double deposit(double balance){ double addSum = 0; system("CLS"); cout<< "Welcome to deposit."<<endl; cout<<"Enter a sum you wish to add to your account:";
[Code] .......
When I withdraw from 30 which is the balance, then i takeSum, for example i take away 30. The balance will become 30 - 30 = 0
When i make another withdraw from example -150, it will be -150.
Which shows correct.
But when i make a deposit from -150 and i addSum 130, the balance shows -500, and it should had been -20.
double withdraw(double balance) { double takeSum = 0; system("CLS"); cout<< "Welcome to withdraw."<<endl; cout<<"Enter a sum you wish to take away from your account:"; cout << balance << '
[Code] .....
What is causing this problem, also when function deposit and withdraw close, it goes to readBalance function, should go to menu.
double readBalance(double balance) { int option; system("CLS"); cout<<"Welcome to balance."<<endl; cout<<"Your balance is:"<<endl;
I wanted to share the value of a variable from Sender Program to Receive after program and want to calculate difference between send and receive. After studying Header file concept I program following three.
Now I am struck. How to to compile? I link all these file. I used following method:
Then I run Sender and after that Receiver.I per my knowledge, Receiver should give difference but it gives error :
Code: Receiver.c: In function "main": Receiver.c:10:42: error: "Send" undeclared (first use in this function) printf(" Total Receive is %d ",Receive-Send);
Code: Sender.c #include <stdio.h> int Send ; void main(){
I have been working a project in C++. I have TTTMain.cpp file that has all the function calls, TTTFuntions.cpp that has all the functions, I have TTT.h file that has all the prototypes and variables and additionally I have Winner.h that has enum class Winner declaration in it. Here is my block of codes:
Winner.h file:
#ifndef winner #define winner enum class Winner {
[Code]....
My question is when I compile this gives me error on
I made my header file. If cpp file with definitions is in project compiler knows it has to be linked, but if it's not compiler doesn't know. If I include standard library or boost I don't have to manually link cpps. How to do so including my header automatically links cpp? Maybe problem is with something else?I use VS 2013.
My socket.cpp program got error. it showed "socket.h: no such file or directory". I had put my header file (socket.h) in the same place with my source file.
I am using the OpenCV library (2.3.1-7) and Qt-Creator (2.4.1) and I have this simplified piece of code that reads in an image as cv::Mat and then applies the OpenCV function pyrDown to the cv::Mat.
#include "opencv2/highgui/highgui.hpp" #include "opencv2/gpu/gpu.hpp" using namespace std; using namespace cv; int main()
[code]....
This piece of code runs just fine and puts out the two different images as exected.
What I need to do now is to retrieve the source code of the "pyrDown"-function and then modify it according to the needs of the project that I am working on.
If I comment out the following line
//#include "opencv2/gpu/gpu.hpp"
then this results in the following error message:
'pyrDown' was not declared in this scope.
Apparently, pyrDown only works if #include "opencv2/gpu/gpu.hpp" is included in my code. Therefore the header of pyrDown should be included in this file, correct?
I am using Qt-Creator and the tooltip text for "pyrDown" is as follows:
Therefore, when i checked the file "/usr/include/opencv2/gpu/gpu.hpp" (which is the complete path to the file), looking for the headers of "pyrDown" I expected to find a matching header.
Those are all the lines of code where the character string "pyrDown" is included.To me, being rather a newbie, it is kind of strange that there is no header that matches the call of the function as it was included in my simplified code example at the very top of this post.
What I would like to understand is the following:
1) Is the file gpu.hpp really the one that stores the header that is used for the call in my code example? If so, I would like to understand why this is the case, since the data types of the parameters seem not to match (eg "GpuMat&" vs. "InputArray"). In gpu.hpp there are other files included, using the "#include"-command, but a text search in those files did not find any strings like "pyrDown" in any of them.
2) If gpu.hpp is not the header file that I am looking for, which one is the correct one and where can I find it?
3) The most important part for me is: Where can I retrieve the corresponding .cpp file for pyrDown, since this is crucial to the progress in my project. I have googled a lot and I found lots of .cpp files that were named "pyrDown.cpp" (example: [URL]), but none of them seems to be the one that I am looking for since either the data types in the header are not in accordance with what I expect or there are #include commands for files that I do not have available on my machine. And I assume that any .cpp-file that tries to use files that are not on my computer can not be the one that is used for the call in the code example at the top of this post.
In file included from /usr/lib/gcc/i686-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/ios_base.h:43:0, from /usr/lib/gcc/i686-redhat-linux/4.5.1/../../../../include/c++/4.5.1/ios:43, from /usr/lib/gcc/i686-redhat-linux/4.5.1/../../../../include/c++/4.5.1/ostream:40, from /usr/lib/gcc/i686-redhat-linux/4.5.1/../../../../include/c++/4.5.1/iostream:40, from player1.cpp:3: /usr/lib/gcc/i686-redhat-linux/4.5.1/../../../../include/c++/4.5.1/bits/locale_classes.h:45:1: error: expected unqualified-id before "namespace"
What does it mean? I am working on classes and this error comes when I run the implentation of my class file.
//Implimentation of class player1 (player.cpp) #include "player1.h" #include <iostream> //using namespace std; void player1 :: Set_Name()
I am having difficulty calling the constructor in interface portion of my program. I get the error: no matching function for call to ‘Node::Node(int, NULL)’ when I try to call it on line 26 within the main function.
code: interface: [URL] implementation: [URL] main file: [URL]
For a big project for school I have to make an airline reservation simulator but I have run into a problem. I want to save the the flight code and its location in a binary file so that I can obtain a code according to the location but this happens:
[URL] ... (link to current output and expected output)
1. Write a program the calculates the volume of a sphere.
Use a define to set Pi to 3.14 and a macro for the formula for the sphere. V = 4/3PiR3. In main ask for the radius (R). Pass it to a function where you calculate the volume and return it to main and print the volume in main. Use float values. (Save this program as you'll need it later.)
