Qualified id in declaration before token ошибка - Не ошибается лишь тот, кто ничего не делает!

This is some crazy error and is giving me a lot of trouble.

#include <iostream>

using namespace std;

class Book {
private:
    int bookid;
    char bookname[50];
    char authorname[50];
    float cost;

public:
    void getinfo(void) {
        for (int i = 0; i < 5; i++) {
            cout << "Enter Book ID" <<endl;
            cin >> bookid;

            cout << "Enter Book Name" << endl;
            cin >> bookname;
            cout << "Enter Author Name" << endl;
            cin >> authorname;
            cout << "Enter Cost" << endl;
            cin >> cost;
        }
    }

    void displayinfo(void);

};


int main()
{
    Book bk[5];
    for (int i = 0; i < 5; i++) {
        bk[i].getinfo();
    }

    void Book::displayinfo() {
        for(int i = 0; i < 5; i++) {
            cout << bk[i].bookid;
            cout << bk[i].bookname;
            cout << bk[i].authorname;
            cout << bk[i].cost;
        }
    }

    return 0;
}

The error, as noted in the title is expected declaration before ‘}’ token at the line void Book::displayinfo() in main

Also this error is coming expected ‘}’ at end of input

asked Aug 28, 2016 at 13:28

Move the function definition void Book::displayinfo(){} out of the main().

Along with this, i have some more suggestion for you. Update your class definition like this

class Book{
private:
  int bookid;
  string bookname; // char bookname[50]; because it can accept book name length more than 50 character. 
  string authorname; // char authorname[50]; because it can accept authorname length more than 50 character. 
  float cost;

public:
    void getinfo(void){
        for(int i =0; i < 5; i++){
            cout << "Enter Book ID" <<endl;
            cin >> bookid;

            cout << "Enter Book Name" << endl;
            getline(cin,bookname); // Because book name can have spaces.
            cout << "Enter Author Name" << endl;
            getline(cin,authorname); // Because author name can have spaces too.
            cout << "Enter Cost" << endl;
            cin >> cost;

        }
    }

    void displayinfo(void);

};

answered Aug 28, 2016 at 14:09

Shravan40Shravan40

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#include "widget.h"
#include "ui_widget.h"
#include <QFileDialog>
#include <QDir>
 
Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);   // Инициализация интерфейса
 
    playlist_model = new QStandardItemModel;   // Модель для хранения названия треков и путей к ним
 
    playlist_model->setHorizontalHeaderLabels(QStringList() <<  // Заголовки для модели (таблицы):
                                              tr("Playlist") <<    // название файла,
                                              tr("Path"));      // путь к файлу
 
    ui->playlist_table->                       // Подключаем модель к интерфейсу
            setModel(playlist_model);          // (т. е. к таблице playlist_table)
 
    ui->playlist_table->hideColumn(1);         // Скрываем колонку с путём к файлу
 
    ui->playlist_table->horizontalHeader()->   // Растягиваем последний видимый заголовок
            setStretchLastSection(true);       // (т. е. "Track")
 
    player = new QMediaPlayer;        // Создаём плеер (все базовые функции плеера)
    playlist = new QMediaPlaylist;    // Создаём плейлист
 
    player->setPlaylist(playlist);    // Подключаем плейлист к плееру
    player->setVolume(50);            // Постоянная громкость 50
 
    /* --------------------------------------------
       TODO: сделать привязку кнопок и слайдеров
    -------------------------------------------- */
    connect(ui->button_previous, &QPushButton::clicked, playlist, &QMediaPlaylist::previous);
    connect(ui->button_next, &QPushButton::clicked, playlist, &QMediaPlaylist::next);
    connect(ui->button_play, &QPushButton::clicked, player, &QMediaPlayer::play);
    connect(ui->button_pause, &QPushButton::clicked, player, &QMediaPlayer::pause);
    connect(ui->button_stop, &QPushButton::clicked, player, &QMediaPlayer::stop);
 
    slider_time = new QSlider;     // Слайдер для перемотки
 
     // Слайдер для громкости
    slider_volume = new QSlider(Qt::Horizontal, this);
    slider_volume->setRange(0, 100);
    slider_volume->setFixedWidth(100);
    slider_volume->setValue(100);
    player = new QMediaPlayer;
    connect(slider_volume, SIGNAL(valueChanged(int)), this, SIGNAL(volumeChanged(int)));
    connect(this, SIGNAL(volumeChanged(int)), player, SLOT(setVolume(int)));
    int Widget::volume() const //Error
    {
        return slider_volume->value();
    }
 
 
    void Widget::setVolume(int volume) //Error
    {
        player->setVolume(volume);
    }
}
 
Widget::~Widget()
{
    delete ui;
    delete player;
    delete playlist;
    delete playlist_model;
    delete slider_time;
    delete slider_volume;
}
/* -----------------------------
   TODO: сделать выборку файлов
------------------------------- */
/* void Widget::addSongs()
{
    ...
}
*/

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Forum
Beginners
qualified-id in declaration before ‘(‘ t

qualified-id in declaration before ‘(‘ token

Write your question here.

hi i am just testing stuff and came across this problem qualified-id in declaration before ‘(‘ token
this is a very small code.. i am a class 0 beginner

main.cpp

#include "test.h"
#include <iostream>
using namespace std;


int main() {
   
    test tc;
    
    cout << "testing output2" <<endl;
cout<<"..................................................................................."<<endl;    


magic mg;

mg.print();


    return 0;
}

................................................................................
 test.cpp


#include "test.h"


test::test() {
    cout<< "i am a constructor"<<endl;
}



test::~test() { // deconstructor have no parameters and no return value no variables.
    cout<<"i am the deconstructor"<<endl;
}

 
 
magic::magic1(){
    
    void magic::print(){
        
        cout<< "regular function"<<endl;
    }
    
}




................................................................................
test.h

#include <iostream>
using namespace std;

#ifndef TEST_H
#define	TEST_H

class test {
public:
    test();
    ~test(); //deconstructor  
private:
};

class magic{
public:
    magic1();
    void print();
private: 
    
};

#endif

thanks

You don’t give the line of the error, but line 73 looks wrong, if it’s meant to be a constructor, the name must be the same as the class, if it isn’t, it needs a return type. You would then also have to change the definition (line 43). Also the term is destructor not deconstructor and you should put include guards at the very start of header files and don’t use using namespace std; in header files (outside of header files it’s your choice but it’s still not a good idea). There’s also no need to put access identifiers if you aren’t going to put anything after them. Finally, proper indenting of code vastly increases readability.

thanks shadowmouse. very helpful!

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Arduino Forum

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Зарегистрирован: 05.12.2015

Здравствуйте, у меня вот такой скетч:

long duration,cm;

void setup()
{
  pinMode (10,OUTPUT);//на реле
pinMode (11, OUTPUT);// триг
pinMode (12, INPUT); //эхо


Serial.begin (9600);
}

void loop() {
duration = pulseIn (12,HIGH);
cm = duration/29/2;

if (cm<20){ digitalWrite(10, HIGH); } //если менее 10см - выключаем


else if (cm<=150) // Если расстояние менее 150 сантиметров 

{ 
   digitalWrite(10, LOW); // Включаем светодиод 
   
  
   delay(500000); //задержка на выключение 
}  
else 
{ 
   digitalWrite(10, HIGH); // иначе выключаем
} 
  }
  
else
{
digitalWrite(10, HIGH);  // включаем LOW
}
Serial.print(cm);
Serial.print("CM");
Serial.println ();
  
delay(100); // делает замер каждые  -- сек

}

При компиляции скетча вылетет такая ошибка:

Arduino: 1.6.0 (Windows 8), Плата»Arduino Mega or Mega 2560, ATmega2560 (Mega 2560)»

HC-SR04.ino:44:1: error: stray » in program

HC-SR04.ino:34:1: error: expected unqualified-id before ‘else’

HC-SR04.ino:38:1: error: ‘Serial’ does not name a type

HC-SR04.ino:39:1: error: ‘Serial’ does not name a type

HC-SR04.ino:40:1: error: ‘Serial’ does not name a type

HC-SR04.ino:42:6: error: expected constructor, destructor, or type conversion before ‘(‘ token

HC-SR04.ino:44:1: error: expected declaration before ‘}’ token

Ошибка компиляции.

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Подскажите пожалуйста что здесь не так. В програмировании я новичёк:)

Не судите строго.

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