Q. Consider the following C declaration.
int x[10], y,z;
What kind of error does following statement contain?
z == x +y;
a. Syntax error
b. Semantic error
c. logical error
d. All of the above
According to me it should be option a, but I am confused, how to get confirm answer with explanation.
I have a Polymorphic class and some child classes, of which I need to make multiple instances of, using a list container. I've set the key type to be a unique pointer of the polymorphic class, and the values of each element pointing to a New Child instance, like so:
std::list<std::unique_ptr<Polymorphic>> polymorphic;
polymorphic.push_back(new Child(foo, bar));
The only problem is that when I try to push_back a new element, I get a compiler error, saying "No instance of overloaded function".Should I try and create a pointer object on it's own and push back that object as an element, it will work fine:
std::unique_ptr<Polymorphic> polym(new Child(foo, bar));
std::list<std::unique_ptr<Polymorphic>> polymorphic;
polymorphic.push_back(polym);
Is there some way I can push a new Child instead of having to create a Polymorphic pointer object and pushing that?
I am getting the error on the implementation of my class name. The error is coming from my parkingControl.cpp 'ParkingControl parkingControlMenu;'. I have used this implementation fine before, but once I added a new main it stopped working. Below is my code.
parkingControl.h
#ifndef PARKINGCONTROL_H_INCLUDED
#define PARKINGCONTROL_H_INCLUDED
#include <iostream>
[Code]....
I have two classes declared as below
#include<iostream>
using namespace std;
Class Node
{
[Code].....
I am trying to write a program that reads in an XML file, parses it and prints out information about each tag. I am getting the following errors when trying to build the program:
Parser.cpp:24:1: error: 'Parser' does not name a type
Parser::getXMLData() {
^
Parser.cpp:120:1: error: 'Parser' does not name a type
Parser:rocessXMLData(
[Code] ....
Here is my code for the 5 files.
[ATTACH]main.cpp
[/ATTACH][ATTACH]Parser.h
[/ATTACH][ATTACH]Parser.cpp
[/ATTACH][ATTACH]Element.h
[/ATTACH][ATTACH]Element.cpp[/ATTACH]
I've verified this on ubuntu 12.10 and on windows/mingw, and found that g++ version 4.7.2 seems to have broken thread/mutex support.
View 11 Replies View RelatedWhen declare and assign an instance of a user-defined struct in a function. And the struct (theStruct) is not declared in the same header file as the function (theFunction). Like this:
files:
"A.h": declares the struct in a class (theClass)
"A.cpp": implements the struct
"B.h": declares the function
"B.cpp": implements the function, error here
I think making the instance (inst) a reference might solve this. But the instance is assigned to a return value from a function (returnFunc). Like:
void theFunction() {
...
theClass::theStruct inst = returnFunc(...);
//returnFunc() returns an instance of theStruct
//the error is at 'inst'
...
}
What do you think?
I have attached the source code I am writing. I have been getting the two following errors. I know it's something to do with the pointer casting.
udp-server.c:174:3: error: subscripted value is neither array nor pointer nor vector
udp-server.c:165:3: error: cannot convert to a pointer type
The file is attached here.
udp-server-edit.txt (7.64K)
Number of downloads: 19
I'm trying to learn recursion, and I'm using a simple array to experiment with it, but I have a couple of annoying errors that I don't understand why they're there. Here's the code:
Code:
#include <cstdlib>
#include <iostream>
using namespace std;
int largest(const int arr[], int lowerIndex, int upperIndex) {
int max;
[code]....
Now try to print the array backwards:
//Use a recursive algorithm to find the largest element in arr:
int largest(arr[], lowerIndex, upperIndex);//error: expected an expression
return 0;
}
I program unix sokcet programming , and part of my code is ti open file from server and open it , but i surprised with this wierd error i dont have any reason for it ?
Code:
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
[Code] ....
File name is : myHeader.h
myHeader.h:24:1: error: unknown type name "File"???
I've been writing the math functions for a 3d game and tried compiling it at about 30 functions in. I get this error related to my pointers to my structures. it affects almost everything in all my functions (as youll see by looking at how i do the math in the function below). The compiler gives me the error
"error: dereferencing pointer to incomplete type"
on all my struct Type4D pointers but referencing the values in my struct TypeMatrix4X4 using pointers seems to work fine i think (it doesn't seem to complian explicitly about it. so here is the important code...
one example function
Code:
struct Type4D *MatVecMult4X4RtoL(struct TypeMatrix4X4 *mat, struct Type4D *vec) {
struct Type4D *dest = (struct Type4D *) malloc(sizeof(struct Type4D));
[Code]....
I am adding int type into vector called "vi" several times like this.
std::vector<int> vi;
void addFunc(int *a, int cnt) {
vi.erase(vi.begin(), vi.end());
vi.clear();
for(int i=0; i<cnt; i++)
vi.push_back(a[i]);
}
and I call the addfunc N times every sec.
And sometimes it has runtime error on vi.push_back line.
(called stack says "_CrtIsValidHeapPointer")
I am having trouble with this program I get the error dereferencing pointer to incomplete type in the populate function I am using BloodShed's Dev C++ compiler v4.9.9.2 I copied this program out of a book because I was having a problem with a linked list in a similar program. I think there is a problem with the compiler not supporting these types of pointer's in a function.
#include <stdio.h>
struct tel_typ {
char name[25];
char phone_no[15];
struct tel_typ *nextaddr;
[code].....
Is the bool keyword in C exactly like the boolean keyword in Java? why this code is getting an 'unknown type error' when I initiialze looping.
#include <stdio.h>
#include <stdlib.h>
int main()
[Code].....
If I am completely using the boolean concept wrong in C, should I just use break statements instead?
I am getting this error:
drivers/media/video/mxc/capture/gt2005.c:2256:62: error: dereferencing pointer to incomplete type
I am at a loss trying to figure this out. Here it is:
case Sensor_Flash:
{
struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
struct sensor *sensor = to_sensor(client);
if (sensor->sensor_io_request && sensor->sensor_io_request->sensor_ioctrl) {
sensor->sensor_io_request->sensor_ioctrl(icd->pdev,Cam_Flash, on);
if(on){
Lines 6 and 7 are giving me the same error. What am I doing wrong?
Below is my code snippet.I'm getting "Error:initialization from incompatible pointer type" error on line 'int *q = status;'.
Obviously, I'm missing something but has no clue...:(
void findwalls(int *p,int y,int x){
int status[y_count][x_count][4];
int *q = status;
for(int i = 0;i < (y_count * x_count * 4);i++)
*(q + i) = *(p + i);
Code:
do {
printf("Edit the entry's cellphone number:");
scanf("%s", addressbook[4][num]);
length = strlen(addressbook[4][num]); //gets the length of the input (should be 10)
//checks if the input is composed of 11 elements wherein the first 2 are 0 and 9 respectively
for(i=0; i<11; i++){
[Code] ....
why do I get an error here?
Code:
if ((addressbook[4][num][0] == '0') && (addressbook[4][num][1] == '9') || (addressbook[4][num][i]>='0') && (addressbook[4][num][i]<='9') && (length=='11'))
And how do I fix this?
The error message is: comparison is always false due to limited data type
I have part of a class that checks to make sure there is a fault that lasts for 60 seconds. The code below is written several times throughout the class for different subsystems dealing with overcurrent.
// Over Current
if (UUV->getCTaps(MOTORCURRPOS_1) > 1.4*UUV->getcurrMode.getMotor().Peak) // The fault {
if (motor1Timer == NULL)
motor1Timer = time(&timer);
else if ( time(&timer) - motor1Timer >= 60)
motor1Over = true;
} else
motor1Timer = NULL;
The timing statement is okay because it works on all of the other fault checkers. It is the if statement that is causing the error I just do not know why.
I am trying to use the Singleton design patterno on Linux, but it is not working:
in the .h I have:
Code:
public:
static ErrorH& Instance();
private:
ErrorH() {};
In the .cpp I have:
Code:
ErrorH& ErrorH::Instance() {
static ErrorH& self = ErrorH();
return self;
}
The errors I get are:
Code:
g++ --g -c ErrorH.cpp -o ErrorH.o
ErrorH.cpp: In static member function "static ErrorH& ErrorH::Instance()":
ErrorH.cpp:9: error: invalid initialization of non-const reference of type "ErrorH&" from a temporary of type "ErrorH"
make: *** [ErrorH.o] Error 1
This code works on Windows, how can I get it to work on Linux?
I am writing a simple program to suck in a txt file then pump it into sql.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Data.OleDb;
using System.Data.SqlClient;
[Code] ......
How I can get past this error and get the data into sql? I read a couple articles on .tag but not sure I understand what to do.
I made a simple binary tree then decide to try out threads too. I got the following error:
call of an object of a class type without appropriate operator or conversion
Code:
#include "Tree.h"
#include <iostream>
#include <thread>
void main(void){
[Code] ....
I am having a hard time figuring out why the error exists. I tried adding the new operator but that did not work.
I have a basic vector/point class where I've overloaded a bunch of arithmetical operators:
Code:
#pragma once
class point {
public:
point() {
}
point(float p_x, float p_y, float p_z) : x(p_x), y(p_y), z(p_z)
[Code] ...
I can use it fine like
Code:
point p(50,50,50);
point q(50,50,50);
point t = p * q + q;
However when I put this point type into a struct and try to access the members after passing it through by const reference:
Code:
struct sextic {
point a,b,c,d,e,f,g;
};
inline static sextic sexticDifference(const sextic &p_sextic1, c
[Code] ....
This gives me an "operator not defined" error for compilation.
error says "cannot convert 'int*' to 'int' in function main()
and also
type mismatch in parameter in function sort(int,int)
Heres the code:
#include<iostream.h>
#include<conio.h>
void main() {
void sort(int,int);
clrscr();
[Code] .....
I'm having some problems with changing an array of numbers of type char to type int. Every time i try to sum 2 array indexed values it returns some letter or symbol. Also, if i change the type of the array in the functions the compiler gives me an error message. I would also like to add that the problem requires that the first two arrays be char so each individual number gets assigned to a different value.
My current code is:
Code:
#include <iostream>
void input(char a[], char b[], int& size_a, int& size_b);
void convert(char a[], int size);
void reverse(char a[], int size);
void add(char a[], char b[], int c[], int size);
int main()
[Code]....
how to convert an element of int type of an array to char type?
View 2 Replies View RelatedI have a function like this:
template<typename T>
void f() {
//...
[Code]....
list contains, in order: A, B and C in any order, D, E
I am thinking it is possible with some clever template and polymorphism combos, but maybe not. As a last resort I know how to make it work by storing static type information in each class, but I'd like to avoid that if possible.