Full disclosure: this is an exercise from "Sams Teach Yourself C++ in 24 Hours" by Jesse Liberty and Rogers Candenhead. This refers to Chapter 9 (Hour 9 Activity 1)
I created a class called Point, in Point.h
I created a class called Rectangle in Rectangle.h and Rectangle.cpp
If I create an int main() function in Rectangle.cpp (that includes Rectangle.h), I can compile Rectangle.cpp and run the resulting program. Fine.
Question:
I create a separate file called main.cpp. I include Rectangle.h. But now the compiler complains.
Code:
$ g++ main.cpp -o main
/tmp/cc38JIph.o: In function `main':
main.cpp:(.text+0x26): undefined reference to `Rectangle::Rectangle(int, int, int, int)'
main.cpp:(.text+0x32): undefined reference to `Rectangle::getArea() const'
collect2: ld returned 1 exit status If I can create a class in Point.h and use it in Rectangle.h, why can I not just use Rectangle in main.cpp?
And the files, of course:
file: main.cpp
Code:
#include <iostream>
#include "Rectangle.h"
using std::cout;
using std::endl;
Having issues with program to create a shape area calculator with circle square and rectangle. the uml goes as follows:
Where the UML has shape as the abstract class with public area():double, getName():string,and getDimensions:string, rectangle derived from shape with protected height, and width, and a public rectangle(h:double, w:double), followed by a derived square from rectangle with just a public square(h:double), and finally a circle derived from shape with a private radius, and a public circle(r:double).
[URL]
Have linked my program and it is giving me the following compiler errors:
error: 'qdebug' was not declared in this scope line 15 of main
error: cannot declare variable 'shp' to be of abstract type 'shape' line 22 of main
error: expected primary-expression before ')' token lines 29 -31 of main
(note previously had qstring as a header file yet changed to string since I was getting error qstring was not declared in this scope.)
I developing a C++ Program to deal with huge data computation. I am using Pointers to hold the data during computation. Current program i developed without using CLASS.
I would like to ask that will the memory usage will be reduced and computational time will be shortened if I modified my program implementing the CLASS into it ?
I have an example where I have a variable belonging to a base class, but I would like to tell the compiler that it actually belongs to a derived class. How can I do this?
// base class: R0 // derived class: R1 // see function SetR1 for the problem class R0 { public: int a;
I know if i will not use the pointer base class function "virtual double grossPay" will be called for both base class object and derived class object and when i will use pointer with reference to the object because base class function is virtual it will look for same function in derived class and if available it will execute it.
Working on a basic class program and I'm generating two compiler errors that I'm not sure how to fix. Header file, implementation cpp and main cpp are shown below. The specific errors are shown after the code.
The file generates the second error, C2228, at lines 37-41 and 43. Basically where I tried using the second created object. Error message is "left of '.setFirstName' must have class/struct/union"
Working on a solution involving inheritance. The whole solution is pretty massive at this point so I'll just focus on the problem areas. I'm getting a lot of "redefinition" and "undefined class type" compiler errors, including C2370, 2011, 2504, and 2027, in Benefit.h, Employee.h (the constant members are a big occurance) I'm also getting 2027 and 2079 in EmployeeMain.cpp. with my Benefit and Employee object calls.
Clearly I missed something in about how to code this correctly. Sadly the course textbook focuses on general OOP theory instead on the accompanying C++ syntax.
My compiler (GCC) keeps expecting an expression where it shouldn't in 1 specific piece of my code:
int zxcNewWindow( HWND parent, TCHAR *text, zxWINDOW *kid, UINT style, int x, int y, int w, int h, int type ) // right here { *kid = zxDefWINDOW;
The project contains only 2 files right now and the settings are just the default for an empty Code::Blocks 12.11 project. Both files are in UTF-8 format (tried in ASCII too), I just cannot see why this is not compiling correctly. I'll post the files in the next two posts.
Edit: For those of you who didn't get what the error was from the above here's the full log:
mingw32-gcc.exe -Wall -g -DzxDEBUG -c C:MePrjscppzxGUImain.c -o objmain.o C:MePrjscppzxGUImain.c: In function 'zxcNewWindow': C:MePrjscppzxGUImain.c:39:10: error: expected expression before '{' token Process terminated with status 1 (0 minutes, 0 seconds) 1 errors, 0 warnings (0 minutes, 0 seconds)
I am trying to run this source code but i am getting the compiler error Expression Must Have a Constant Value. I tried making both the variables x and y constants and assigned them to a significantly big number but then i am getting the error expression must be a modifiable lvalue.I have made comments in the code in front where Visual Studio is giving me the syntax error (red squiggly line).
#include<iostream> #include <string> #include<cmath> using namespace std; int main(){ int x; int y;
I am having problems compiling this program. line 29 causes the error "left operand must be l-value".
// chap5proj.cpp : Defines the entry point for the console application. // # include <stdafx.h> # include <iostream> using namespace std; int main() { double mph, time, disPerHour, milesTrav;
Well, I thought I had this program working but now I'm getting the above referenced compiler error. The program is just a basic user interface. It is for a classwork assignment.
The program is to accept user information as a string, convert it (if needed) to either the int or double variable, and then display the result. I'm using stringstream convert to make the change between types, but I'm not sure if I'm using it right (that might be what's causing the error, I'm not sure). Line 36-37 generates the error.
Code: #include <iostream> #include <iomanip> #include <sstream> using namespace std;
I am trying to compile the files file1.c and file2.c using Mingw (gcc)
///////////////////// header.h //////////////////// #ifndef header #define header int variable; #endif
[Code] ....
I would have expected a multiple defnition error when linking the two .c files. as in both the files, with the 'int variable' command, the variable 'variable' is defined (memory allocated) and during linking the linker doesnot know which variable to link to.
I get an error though when i use "int variable =123;" in the header file instead of the "int variable;" statement. i dont understand as in both the cases the variable is defined (memory is allocated) and the linker should give a multiple definition error.
I have been implementing a Hash Table class made, and ran into a bit of a problem in my Delete function. I have the hash table made up as
vector<list<HashNode<T,X>>> m_Table
My problem is when I iterate through the vector, and then the list in that current element to try and find the Node I want to delete, the STL list class gives me the error:
Error1error C2678: binary '==' : no operator found which takes a left-hand operand of type 'HashNode<T,X>' (or there is no acceptable conversion)
I have an issue. VS 2013 isn't recognizing objects that I've declared when I use class functions.I'm getting this error: "Line 14 and 15: Error C2228: left of '.asciiToFpc6' must have class/struct/union"...Here's the relevant code:
Additionally VS apparently doesn't like my bitwise operators in my class functions and doesn't think they're doing anything. It gives "warning C4552: ['|', '<<', '>>', '&'] : operator has no effect; expected operator with side-effect" for all of them, but it seems to me the code should work fine and actually accomplish things....
I have read the book over and over and I thought I understand "CLASS". But when I applied it and write the code the compiler tells me that there is a compiling error.
1. I have this method addProduct(Product* pProduct) in a Class called ProductRack, the code is in ProductRack.cpp file. The declaration of the Class methods and private variables are in ProductRack.h header file.
2. But when I call a method in the DeliveryCHute Class from the ProductRack Class I get a compiler errors which are these:
A.IntelliSense: a nonstatic member reference must be relative to a specific object B.error C2352: 'Project1::DeliveryChute::insertProduct' : illegal call of non-static member function
And this is causing the error:
if (Project1::DeliveryChute::insertProduct(pProduct) == false)
//THIS IS JUST ONE METHOD INSIDE ProductRack.cpp bool Project1::ProductRack::addProduct(Product* pProduct) { // Todo : Implementing if (Project1::DeliveryChute::insertProduct(pProduct) == false) return true;
I am trying to make a simple program for encrypting a char* with the XOR operator. The code compiles and links perfectly, but I get an Access violation runtime error:
#include <iostream> #include <cstdlib> #include <cstdio> #include <string> #include <fstream> using namespace std; int main(int argc, char** argv) {
I created a program to convert files to XML. This if statement is giving me some trouble. I am trying to replace all &s with the XML & so that &s will work in the entities of the XML file. Some entities have more than 1 &. With those which have more than one I get an output like this: <cit:district>Anambra & Enugu & Eb</cit:district> .
I am trying to write a program that will take a list of integers from a file and write them to another text file. I've been banging my head at this for days trying to get it to compile as it is riddled with linker and compiler errors.
