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C++ incomprehensible compiler errors

I got a pretty simple task to do. Write a class that defines time. For some reason, in one of the functions I get an error, that I do not understand.
I searched for a solution with no success, so in the end I decided post it here.

time.h

class time
{
private:
    int _hours;
    int _minutes;
    float _seconds;
    bool checkHours(int hours);
    bool checkMinutes(int minutes);
    bool checkSeconds(float seconds);

public:

time(int hours=0, int minutes=0, float seconds=0);
time(const time & tm);
~time();


void hours(int hours);
int  hours() const;
void minutes(int minutes);
int  minutes() const;
void seconds(float seconds);
float  seconds() const;


void operator=(time tm);
bool operator==(time tm);


void print();
time getTimeFromUser();
float getTimeAsFractionOfTheDay(time tm);

};

and time.cpp

#include <iostream>
#include "time.h"

bool time::checkHours(int hours)
{
    return hours>=0 && hours<24;
}
bool time::checkMinutes(int MS)
{
    return MS>=0 && MS<60;
}
bool time::checkSeconds(float MS)
{
    return MS>=0 && MS<60;
}

//constractors
time::time(int hours, int minutes, float seconds)
{
    if(checkHours(hours) && checkMinutes(minutes) && checkSeconds(seconds))
    {
        _hours=hours;
        _minutes=minutes;
        _seconds=seconds;
    }
    else
    {
        cout<<"Error"<<endl; _hours=-1; _minutes=-1; _seconds=-1;
    }
}
time::time(const time & tm)
{
    _seconds = tm.seconds();
    _hours = tm.hours();
    _minutes=tm.minutes();
}
time::~time()
{
}

//get-set functions
void time::hours(int hours)
{
    _hours=hours;
}
int  time::hours() const
{
    return _hours;
}
void time::minutes(int minutes)
{
    _minutes=minutes;
}
int  time::minutes() const
{
    return _minutes;
}
void time::seconds(float seconds)
{
    _seconds = seconds;
}

float  time::seconds() const
{
    return _seconds;
}

//operators
void time::operator=(time tm)
{

    _hours=tm.hours();
    _minutes=tm.minutes();
    _seconds=tm.seconds();

}
bool time::operator==(time tm)
{
    return _hours=tm.hours() && _minutes==tm.minutes() && _seconds==tm.seconds();
}

//some function
void time::print()
{
    cout<<" "<<_hours<<":"<<_minutes<<":"<<_seconds<<" "<<endl;
}

time time::getTimeFromUser()
{
    time newTime;
    int userhours=-1;
    int userminutes=-1;
    float userseconds=-1;
    while (!checkHours(userhours))
    {
        cout<<"enter hours"<<endl;
        cin>>userhours;
        if(!checkHours(userhours))
        {
            cout<<"Error try again"<<endl;
        }
    }

    while (!checkMinutes(userminutes))
    {
        cout<<"enter minutes"<<endl;
        cin>>userminutes;
        if(!checkMinutes(userminutes))
        {
            cout<<"Error try again"<<endl;
        }
    }

    while (!checkSeconds(userseconds))
    {
        cout<<"enter Seconds"<<endl;
        cin>>userseconds;
        if(!checkSeconds(userseconds))
        {
            cout<<"Error try again"<<endl;
        }
    }

    newTime.seconds(userseconds);
    newTime.hours(userhours);
    newTime.minutes(userminutes);

    return newTime;
}


float time::getTimeAsFractionOfTheDay(time tm)
{

    return 0.0;
}

And i got those errors

在此输入图像描述

I don't understand what I did wrong. I think it's something stupid but I can't find it.

As it turns out, you are the victim of a subtle bug.

time is a function declared in the system header time.h , which is getting included in your program via iostream . When you declare time time::getTimeFromUser() , the compiler sees the return value and thinks you mean the function time!

clang makes this obvious with its error:

time.cpp:122:1: error: must use 'class' tag to refer to type 'time' in this scope
time time::getTimeFromUser()
^
class 
/usr/include/time.h:133:8: note: class 'time' is hidden by a non-type declaration of 'time' here
time_t time(time_t *);
       ^

The fix is to define that particular function like this:

class time time::getTimeFromUser() {
    ...
}

Or, if using C++11,

auto time::getTimeFromUser() -> time {
    ...
}

First problem:

bool time::operator==(time tm)
{
    return _hours=tm.hours() && _minutes==tm.minutes() && _seconds==tm.seconds();
//               ^
}

There should be a comparison operator there, not an assignment:

bool time::operator==(time tm)
{
    return _hours==tm.hours()
//               ^^
                   && _minutes==tm.minutes() && _seconds==tm.seconds();
}

Second problem:

You are using cout and endl , which belong to the std namespace, without a using declaration or a using directive.

You should add the following before using cout , cin , and endl as unqualified name:

using std::cout;
using std::endl;
using std::cin;

Alternatively, you can choose to fully qualify their names when using them. For instance:

    std::cout<<"Error"<<endl; _hours=-1; _minutes=-1; _seconds=-1;
//  ^^^^^

the problemm is that your header is time.h (already take as a standard header). You think you get the one you declared but you get the standard one. thereofore, you don't have the declaration of your class but the standard header. Rename it Test.h and Tes.cpp and it will work And also add using namespace std on the top of your cpp file

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