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//#define XERR
#include "main.ih"
void show(std::error_category &cat)
{
std::cerr << cat.name() << '\n'; // show the name of the category
}
int main(int argc, char **argv)
try
{
Category &cat = Category::instance();
cout << cat.name() << '\n'; // show the name of the category
show(cat); // same, with overridden name()
error_code ec = CatErr::Err2; // initialize an error_code
ec = CatErr::Err2; // same, direct assignment
// same, using assign()
ec.assign(static_cast<int>(CatErr::Err2), cat);
cout <<
"ec == Err2 ? " << (ec == CatErr::Err2) << "\n"
"ec == Err1 ? " << (ec == CatErr::Err1) << "\n"
"ec == Cond1 ? " << (ec == Cond::Cond1) << "\n"
"ec == Cond2 ? " << (ec == Cond::Cond2) << "\n"
"ec == Cond3 ? " << (ec == Cond::Cond3) << "\n"
"ec == Cond ? " << (ec == Cond{}) << "\n"
"ec == errc ? " << (ec == errc::not_enough_memory) << "\n"
// WC "ec == 1 ? " << (ec == 1) << "\n"
;
cout << "error_code value: " << ec.value() <<
", equivalent called from error_code: " <<
ec.category().equivalent(ec, static_cast<int>(Cond::Cond1)) <<
'\n';
cout << "Enum value of Cond::NoCond = " <<
error_condition{ Cond::NoCond }.value() << '\n';
cout << "Default Cond value: " << (int)Cond{} << '\n';
assert(ec != Cond::Cond1); // OK, current Cond value == Cond2
assert(ec == Cond::Cond2); // OK, current Cond value == Cond2
assert(ec != Cond{}); // OK,
assert(ec == CatErr::Err2);
// assert(ec == 2); // not OK: can't compare to int
// assert(ec == CatErr::Err1); // not OK: ec == Err2
cout << ec.category().name() << '\n'; // name via category()
// get the default error condition
error_condition cond = ec.default_error_condition();
error_condition nope{ 12, cat }; // validity not checked
cout << nope.value() << '\n'; // shows 12
cout << "Default error condition:\n"
" cat.: " << cond.category().name() << "\n" // the cat. name
" value: " << cond.value() << "\n" // CatErr's numeric value
" " << cond.message() << '\n'; // CatErr's name
error_condition errCond{ Cond::Cond1 };
cout << "Directly constructed error condition. Value = " <<
errCond.value() << ", message = " << errCond.message() << '\n';
cout << "Making error condition objects, showing their value:\n"
"Cond::Cond1: " << make_error_condition(Cond::Cond1).value() <<
"\n"
"Cond::Cond2: " << make_error_condition(Cond::Cond2).value() <<
'\n';
throw system_error{ ec, "For demonstration purposes" };
}
catch (std::system_error const &se)
{
std::cout << "System Error:\n"
" what() = " << se.what() << "\n"
" (error_)code = " << se.code() << '\n';
}
catch (...)
{
cout << "unexpected exception\n";
return 1;
}
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