I'm writing the following class
class Date {
int day, month, year;
int month31[7] = {1,3,5,7,8,10,12};
int size31 = 7;
int month30[4] = {4,6,9,11};
int size30 = 4;
bool isLeapYear(int yr);
bool inArray(int val, int *arr, int arrSize);
public:
Date(int d, int m, int y);
Date operator ++ ();
Date operator ++ (int);
friend ostream &operator << (ostream &out, Date &d);
void display() const
{
cout <<day<<"-"<<month<<"-"<<year<<endl;
}
};
These are some of the functions.
Date:: Date(int d, int m, int y)
{
day = d;
month = m;
year = y;
}
Date Date:: operator ++ ()
{
day += 1;
if (month == 2) {
if (!isLeapYear(year) && day > 28) {
month += 1; day = 1;
} else if (isLeapYear(year) && day > 29) {
month += 1; day = 1;
}
} else if (day > 30 and inArray(month, month30, size30)) {
month += 1; day = 1;
} else if (day > 31 and inArray(month, month31, size31)) {
month += 1; day = 1;
}
if (month > 12) {
year += 1; month = 1;
}
return (*this);
}
Date Date:: operator ++ (int)
{
Date tmp = *this;
++(*this);
return tmp;
}
Here I tried to overload the << operator.
ostream &operator << (ostream &out, Date &d)
{
out << d.day <<"-"<< d.month <<"-"<< d.year;
return out;
}
I created an object d1 of class Date. Now when I'm doing
cout << d1 << endl;
from main(), it is working fine. But if I do something like
cout << (++d1) << endl;
or
cout << (d++) << endl;
I'm getting errors while compilation. (I don't think is is a problem with the overloaded increment operator because when I do (++d1).display or (d1++).display(), It is working fine.)
Anyway, when I'm using cout (with increment), I'm getting this super big error message.
p04.cpp: In function ‘int main()’:
p04.cpp:129:10: error: no match for ‘operator<<’ (operand types are ‘std::ostream’ {aka ‘std::basic_ostream<char>’} and ‘Date’)
129 | cout << (++d5) <<endl;
| ~~~~ ^~ ~~~~~~
| | |
| | Date
| std::ostream {aka std::basic_ostream<char>}
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:108:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::basic_ostream<_CharT, _Traits>::__ostream_type& (*)(std::basic_ostream<_CharT, _Traits>::__ostream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
108 | operator<<(__ostream_type& (*__pf)(__ostream_type&))
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:108:36: note: no known conversion for argument 1 from ‘Date’ to ‘std::basic_ostream<char>::__ostream_type& (*)(std::basic_ostream<char>::__ostream_type&)’ {aka ‘std::basic_ostream<char>& (*)(std::basic_ostream<char>&)’}
108 | operator<<(__ostream_type& (*__pf)(__ostream_type&))
| ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/11.1.0/ostream:117:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::basic_ostream<_CharT, _Traits>::__ios_type& (*)(std::basic_ostream<_CharT, _Traits>::__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>; std::basic_ostream<_CharT, _Traits>::__ios_type = std::basic_ios<char>]’
117 | operator<<(__ios_type& (*__pf)(__ios_type&))
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:117:32: note: no known conversion for argument 1 from ‘Date’ to ‘std::basic_ostream<char>::__ios_type& (*)(std::basic_ostream<char>::__ios_type&)’ {aka ‘std::basic_ios<char>& (*)(std::basic_ios<char>&)’}
117 | operator<<(__ios_type& (*__pf)(__ios_type&))
| ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
/usr/include/c++/11.1.0/ostream:127:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::ios_base& (*)(std::ios_base&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
127 | operator<<(ios_base& (*__pf) (ios_base&))
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:127:30: note: no known conversion for argument 1 from ‘Date’ to ‘std::ios_base& (*)(std::ios_base&)’
127 | operator<<(ios_base& (*__pf) (ios_base&))
| ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
/usr/include/c++/11.1.0/ostream:166:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long int) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
166 | operator<<(long __n)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:166:23: note: no known conversion for argument 1 from ‘Date’ to ‘long int’
166 | operator<<(long __n)
| ~~~~~^~~
/usr/include/c++/11.1.0/ostream:170:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
170 | operator<<(unsigned long __n)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:170:32: note: no known conversion for argument 1 from ‘Date’ to ‘long unsigned int’
170 | operator<<(unsigned long __n)
| ~~~~~~~~~~~~~~^~~
/usr/include/c++/11.1.0/ostream:174:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(bool) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
174 | operator<<(bool __n)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:174:23: note: no known conversion for argument 1 from ‘Date’ to ‘bool’
174 | operator<<(bool __n)
| ~~~~~^~~
In file included from /usr/include/c++/11.1.0/ostream:853,
from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/bits/ostream.tcc:91:5: note: candidate: ‘std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(short int) [with _CharT = char; _Traits = std::char_traits<char>]’
91 | basic_ostream<_CharT, _Traits>::
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/11.1.0/bits/ostream.tcc:92:22: note: no known conversion for argument 1 from ‘Date’ to ‘short int’
92 | operator<<(short __n)
| ~~~~~~^~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:181:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(short unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
181 | operator<<(unsigned short __n)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:181:33: note: no known conversion for argument 1 from ‘Date’ to ‘short unsigned int’
181 | operator<<(unsigned short __n)
| ~~~~~~~~~~~~~~~^~~
In file included from /usr/include/c++/11.1.0/ostream:853,
from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/bits/ostream.tcc:105:5: note: candidate: ‘std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(int) [with _CharT = char; _Traits = std::char_traits<char>]’
105 | basic_ostream<_CharT, _Traits>::
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/11.1.0/bits/ostream.tcc:106:20: note: no known conversion for argument 1 from ‘Date’ to ‘int’
106 | operator<<(int __n)
| ~~~~^~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:192:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
192 | operator<<(unsigned int __n)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:192:31: note: no known conversion for argument 1 from ‘Date’ to ‘unsigned int’
192 | operator<<(unsigned int __n)
| ~~~~~~~~~~~~~^~~
/usr/include/c++/11.1.0/ostream:201:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
201 | operator<<(long long __n)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:201:28: note: no known conversion for argument 1 from ‘Date’ to ‘long long int’
201 | operator<<(long long __n)
| ~~~~~~~~~~^~~
/usr/include/c++/11.1.0/ostream:205:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
205 | operator<<(unsigned long long __n)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:205:37: note: no known conversion for argument 1 from ‘Date’ to ‘long long unsigned int’
205 | operator<<(unsigned long long __n)
| ~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/11.1.0/ostream:220:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(double) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
220 | operator<<(double __f)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:220:25: note: no known conversion for argument 1 from ‘Date’ to ‘double’
220 | operator<<(double __f)
| ~~~~~~~^~~
/usr/include/c++/11.1.0/ostream:224:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(float) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
224 | operator<<(float __f)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:224:24: note: no known conversion for argument 1 from ‘Date’ to ‘float’
224 | operator<<(float __f)
| ~~~~~~^~~
/usr/include/c++/11.1.0/ostream:232:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long double) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
232 | operator<<(long double __f)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:232:30: note: no known conversion for argument 1 from ‘Date’ to ‘long double’
232 | operator<<(long double __f)
| ~~~~~~~~~~~~^~~
/usr/include/c++/11.1.0/ostream:245:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(const void*) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>]’
245 | operator<<(const void* __p)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:245:30: note: no known conversion for argument 1 from ‘Date’ to ‘const void*’
245 | operator<<(const void* __p)
| ~~~~~~~~~~~~^~~
/usr/include/c++/11.1.0/ostream:250:7: note: candidate: ‘std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::nullptr_t) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__ostream_type = std::basic_ostream<char>; std::nullptr_t = std::nullptr_t]’
250 | operator<<(nullptr_t)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:250:18: note: no known conversion for argument 1 from ‘Date’ to ‘std::nullptr_t’
250 | operator<<(nullptr_t)
| ^~~~~~~~~
In file included from /usr/include/c++/11.1.0/ostream:853,
from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/bits/ostream.tcc:119:5: note: candidate: ‘std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(std::basic_ostream<_CharT, _Traits>::__streambuf_type*) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_ostream<_CharT, _Traits>::__streambuf_type = std::basic_streambuf<char>]’
119 | basic_ostream<_CharT, _Traits>::
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/11.1.0/bits/ostream.tcc:120:34: note: no known conversion for argument 1 from ‘Date’ to ‘std::basic_ostream<char>::__streambuf_type*’ {aka ‘std::basic_streambuf<char>*’}
120 | operator<<(__streambuf_type* __sbin)
| ~~~~~~~~~~~~~~~~~~^~~~~~
In file included from /usr/include/c++/11.1.0/bits/basic_string.h:48,
from /usr/include/c++/11.1.0/string:55,
from /usr/include/c++/11.1.0/bits/locale_classes.h:40,
from /usr/include/c++/11.1.0/bits/ios_base.h:41,
from /usr/include/c++/11.1.0/ios:42,
from /usr/include/c++/11.1.0/ostream:38,
from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/string_view:665:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, std::basic_string_view<_CharT, _Traits>)’
665 | operator<<(basic_ostream<_CharT, _Traits>& __os,
| ^~~~~~~~
/usr/include/c++/11.1.0/string_view:665:5: note: template argument deduction/substitution failed:
p04.cpp:129:18: note: ‘Date’ is not derived from ‘std::basic_string_view<_CharT, _Traits>’
129 | cout << (++d5) <<endl;
| ^
In file included from /usr/include/c++/11.1.0/string:55,
from /usr/include/c++/11.1.0/bits/locale_classes.h:40,
from /usr/include/c++/11.1.0/bits/ios_base.h:41,
from /usr/include/c++/11.1.0/ios:42,
from /usr/include/c++/11.1.0/ostream:38,
from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/bits/basic_string.h:6517:5: note: candidate: ‘template<class _CharT, class _Traits, class _Alloc> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>&)’
6517 | operator<<(basic_ostream<_CharT, _Traits>& __os,
| ^~~~~~~~
/usr/include/c++/11.1.0/bits/basic_string.h:6517:5: note: template argument deduction/substitution failed:
p04.cpp:129:18: note: ‘Date’ is not derived from ‘const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>’
129 | cout << (++d5) <<endl;
| ^
In file included from /usr/include/c++/11.1.0/bits/ios_base.h:46,
from /usr/include/c++/11.1.0/ios:42,
from /usr/include/c++/11.1.0/ostream:38,
from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/system_error:263:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const std::error_code&)’
263 | operator<<(basic_ostream<_CharT, _Traits>& __os, const error_code& __e)
| ^~~~~~~~
/usr/include/c++/11.1.0/system_error:263:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘const std::error_code&’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:506:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, _CharT)’
506 | operator<<(basic_ostream<_CharT, _Traits>& __out, _CharT __c)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:506:5: note: template argument deduction/substitution failed:
p04.cpp:129:18: note: deduced conflicting types for parameter ‘_CharT’ (‘char’ and ‘Date’)
129 | cout << (++d5) <<endl;
| ^
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:511:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, char)’
511 | operator<<(basic_ostream<_CharT, _Traits>& __out, char __c)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:511:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘char’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:517:5: note: candidate: ‘template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, char)’
517 | operator<<(basic_ostream<char, _Traits>& __out, char __c)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:517:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘char’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:523:5: note: candidate: ‘template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, signed char)’
523 | operator<<(basic_ostream<char, _Traits>& __out, signed char __c)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:523:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘signed char’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:528:5: note: candidate: ‘template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, unsigned char)’
528 | operator<<(basic_ostream<char, _Traits>& __out, unsigned char __c)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:528:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘unsigned char’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:589:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const _CharT*)’
589 | operator<<(basic_ostream<_CharT, _Traits>& __out, const _CharT* __s)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:589:5: note: template argument deduction/substitution failed:
p04.cpp:129:18: note: mismatched types ‘const _CharT*’ and ‘Date’
129 | cout << (++d5) <<endl;
| ^
In file included from /usr/include/c++/11.1.0/ostream:853,
from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/bits/ostream.tcc:321:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const char*)’
321 | operator<<(basic_ostream<_CharT, _Traits>& __out, const char* __s)
| ^~~~~~~~
/usr/include/c++/11.1.0/bits/ostream.tcc:321:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘const char*’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:606:5: note: candidate: ‘template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, const char*)’
606 | operator<<(basic_ostream<char, _Traits>& __out, const char* __s)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:606:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘const char*’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:619:5: note: candidate: ‘template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, const signed char*)’
619 | operator<<(basic_ostream<char, _Traits>& __out, const signed char* __s)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:619:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘const signed char*’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:624:5: note: candidate: ‘template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, const unsigned char*)’
624 | operator<<(basic_ostream<char, _Traits>& __out, const unsigned char* __s)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:624:5: note: template argument deduction/substitution failed:
p04.cpp:129:14: note: cannot convert ‘d5.Date::operator++()’ (type ‘Date’) to type ‘const unsigned char*’
129 | cout << (++d5) <<endl;
| ~^~~~~
In file included from /usr/include/c++/11.1.0/iostream:39,
from p04.cpp:1:
/usr/include/c++/11.1.0/ostream:773:5: note: candidate: ‘template<class _Ostream, class _Tp> typename std::enable_if<std::__and_<std::__not_<std::is_lvalue_reference<_Tp> >, std::__is_convertible_to_basic_ostream<_Ostream>, std::__is_insertable<typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type, const _Tp&, void> >::value, typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type>::type std::operator<<(_Ostream&&, const _Tp&)’
773 | operator<<(_Ostream&& __os, const _Tp& __x)
| ^~~~~~~~
/usr/include/c++/11.1.0/ostream:773:5: note: template argument deduction/substitution failed:
/usr/include/c++/11.1.0/ostream: In substitution of ‘template<class _Ostream, class _Tp> typename std::enable_if<std::__and_<std::__not_<std::is_lvalue_reference<_Tp> >, std::__is_convertible_to_basic_ostream<_Ostream>, std::__is_insertable<typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type, const _Tp&, void> >::value, typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type>::type std::operator<<(_Ostream&&, const _Tp&) [with _Ostream = std::basic_ostream<char>&; _Tp = Date]’:
p04.cpp:129:18: required from here
/usr/include/c++/11.1.0/ostream:773:5: error: no type named ‘type’ in ‘struct std::enable_if<false, std::basic_ostream<char>&>’
p04.cpp:84:10: note: candidate: ‘std::ostream& operator<<(std::ostream&, Date&)’ (near match)
84 | ostream &operator << (ostream &out, Date &d)
| ^~~~~~~~
p04.cpp:84:10: note: conversion of argument 2 would be ill-formed:
p04.cpp:129:14: error: cannot bind non-const lvalue reference of type ‘Date&’ to an rvalue of type ‘Date’
129 | cout << (++d5) <<endl;
| ~^~~~~
So, where did I go wrong ?
