C++

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Reference

• C library:

  • <cassert> (assert.h)
  • <cctype> (ctype.h)
  • <cerrno> (errno.h)
  • C++11
    <cfenv> (fenv.h)
  • <cfloat> (float.h)
  • C++11
    <cinttypes> (inttypes.h)
  • <ciso646> (iso646.h)
  • <climits> (limits.h)
  • <clocale> (locale.h)
  • <cmath> (math.h)
  • <csetjmp> (setjmp.h)
  • <csignal> (signal.h)
  • <cstdarg> (stdarg.h)
  • C++11
    <cstdbool> (stdbool.h)
  • <cstddef> (stddef.h)
  • C++11
    <cstdint> (stdint.h)
  • <cstdio> (stdio.h)
  • <cstdlib> (stdlib.h)
  • <cstring> (string.h)
  • C++11
    <ctgmath> (tgmath.h)
  • <ctime> (time.h)
  • C++11
    <cuchar> (uchar.h)
  • <cwchar> (wchar.h)
  • <cwctype> (wctype.h)

• Containers:

  • C++11
    <array>
  • <deque>
  • C++11
    <forward_list>
  • <list>
  • <map>
  • <queue>
  • <set>
  • <stack>
  • C++11
    <unordered_map>
  • C++11
    <unordered_set>
  • <vector>

• Input/Output:

  • <fstream>
  • <iomanip>
  • <ios>
  • <iosfwd>
  • <iostream>
  • <istream>
  • <ostream>
  • <sstream>
  • <streambuf>

• Multi-threading:

  • C++11
    <atomic>
  • C++11
    <condition_variable>
  • C++11
    <future>
  • C++11
    <mutex>
  • C++11
    <thread>

• Other:

  • <algorithm>
  • <bitset>
  • C++11
    <chrono>
  • C++11
    <codecvt>
  • <complex>
  • <exception>
  • <functional>
  • C++11
    <initializer_list>
  • <iterator>
  • <limits>
  • <locale>
  • <memory>
  • <new>
  • <numeric>
  • C++11
    <random>
  • C++11
    <ratio>
  • C++11
    <regex>
  • <stdexcept>
  • <string>
  • C++11
    <system_error>
  • C++11
    <tuple>
  • C++11
    <type_traits>
  • C++11
    <typeindex>
  • <typeinfo>
  • <utility>
  • <valarray>

<system_error>

• classes

  • C++11
    error_category
  • C++11
    error_code
  • C++11
    error_condition
  • C++11
    is_error_code_enum
  • C++11
    is_error_condition_enum
  • C++11
    system_error

• enum classes

  • C++11
    errc

• functions

  • C++11
    generic_category
  • C++11
    make_error_code
  • C++11
    make_error_condition
  • C++11
    system_category

error_code

• C++11
  error_code::error_code

• member functions

  • C++11
    error_code::assign
  • C++11
    error_code::category
  • C++11
    error_code::clear
  • C++11
    error_code::default_error_condition
  • C++11
    error_code::message
  • C++11
    error_code::operator bool
  • C++11
    error_code::operator=
  • C++11
    error_code::value

• non-member overloads

  • C++11
    operator<<
  • C++11
    relational operators (error_code)

• non-member specializations

  • C++11
    hash<error_code>

std::error_code::operator bool

explicit operator bool() const noexcept;

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// error_code::operator bool
#include <iostream>       // std::cout
#include <cerrno>         // errno
#include <system_error>   // std::error_code, std::generic_category
#include <cmath>          // std::pow

struct expnumber {
  double value;
  std::error_code error;
  expnumber (double base, double exponent) {
    value = std::pow(base,exponent);
    if (errno) error.assign (errno,std::generic_category());
  }
};

int main()
{
  expnumber foo (3.0, 2.0), bar (3.0, 10e6);

  std::cout << "foo: ";
  if (!foo.error) std::cout << foo.value << '\n';
  else std::cout << "Error: " << foo.error.message() << '\n';

  std::cout << "bar: ";
  if (!bar.error) std::cout << bar.value << '\n';
  else std::cout << "Error: " << bar.error.message() << '\n';

  return 0;
}

foo: 9
bar: Error: Result too large