type_traits.hpp
#ifndef PROTON_INTERNAL_TYPE_TRAITS_HPP
#define PROTON_INTERNAL_TYPE_TRAITS_HPP
/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
#include "./config.hpp"
#include "../types_fwd.hpp"
#include "../type_id.hpp"
namespace proton {
namespace internal {
class decoder;
class encoder;
template <bool, class T=void> struct enable_if {};
template <class T> struct enable_if<true, T> { typedef T type; };
struct true_type { static const bool value = true; };
struct false_type { static const bool value = false; };
template <class T> struct is_integral : public false_type {};
template <class T> struct is_signed : public false_type {};
template <> struct is_integral<char> : public true_type {};
template <> struct is_signed<char> : public false_type {};
template <> struct is_integral<unsigned char> : public true_type {};
template <> struct is_integral<unsigned short> : public true_type {};
template <> struct is_integral<unsigned int> : public true_type {};
template <> struct is_integral<unsigned long> : public true_type {};
template <> struct is_integral<signed char> : public true_type {};
template <> struct is_integral<signed short> : public true_type {};
template <> struct is_integral<signed int> : public true_type {};
template <> struct is_integral<signed long> : public true_type {};
template <> struct is_signed<unsigned short> : public false_type {};
template <> struct is_signed<unsigned int> : public false_type {};
template <> struct is_signed<unsigned long> : public false_type {};
template <> struct is_signed<signed char> : public true_type {};
template <> struct is_signed<signed short> : public true_type {};
template <> struct is_signed<signed int> : public true_type {};
template <> struct is_signed<signed long> : public true_type {};
#if PN_CPP_HAS_LONG_LONG
template <> struct is_integral<unsigned long long> : public true_type {};
template <> struct is_integral<signed long long> : public true_type {};
template <> struct is_signed<unsigned long long> : public false_type {};
template <> struct is_signed<signed long long> : public true_type {};
#endif
template <class T, class U> struct is_same { static const bool value=false; };
template <class T> struct is_same<T,T> { static const bool value=true; };
template< class T > struct remove_const { typedef T type; };
template< class T > struct remove_const<const T> { typedef T type; };
template <type_id ID, class T> struct type_id_constant {
typedef T type;
static const type_id value = ID;
};
template <class T> struct type_id_of;
template<> struct type_id_of<bool> : public type_id_constant<BOOLEAN, bool> {};
template<> struct type_id_of<uint8_t> : public type_id_constant<UBYTE, uint8_t> {};
template<> struct type_id_of<int8_t> : public type_id_constant<BYTE, int8_t> {};
template<> struct type_id_of<uint16_t> : public type_id_constant<USHORT, uint16_t> {};
template<> struct type_id_of<int16_t> : public type_id_constant<SHORT, int16_t> {};
template<> struct type_id_of<uint32_t> : public type_id_constant<UINT, uint32_t> {};
template<> struct type_id_of<int32_t> : public type_id_constant<INT, int32_t> {};
template<> struct type_id_of<uint64_t> : public type_id_constant<ULONG, uint64_t> {};
template<> struct type_id_of<int64_t> : public type_id_constant<LONG, int64_t> {};
template<> struct type_id_of<wchar_t> : public type_id_constant<CHAR, wchar_t> {};
template<> struct type_id_of<float> : public type_id_constant<FLOAT, float> {};
template<> struct type_id_of<double> : public type_id_constant<DOUBLE, double> {};
template<> struct type_id_of<timestamp> : public type_id_constant<TIMESTAMP, timestamp> {};
template<> struct type_id_of<decimal32> : public type_id_constant<DECIMAL32, decimal32> {};
template<> struct type_id_of<decimal64> : public type_id_constant<DECIMAL64, decimal64> {};
template<> struct type_id_of<decimal128> : public type_id_constant<DECIMAL128, decimal128> {};
template<> struct type_id_of<uuid> : public type_id_constant<UUID, uuid> {};
template<> struct type_id_of<std::string> : public type_id_constant<STRING, std::string> {};
template<> struct type_id_of<symbol> : public type_id_constant<SYMBOL, symbol> {};
template<> struct type_id_of<binary> : public type_id_constant<BINARY, binary> {};
template <class T, class Enable=void> struct has_type_id : public false_type {};
template <class T> struct has_type_id<T, typename type_id_of<T>::type> : public true_type {};
// The known/unknown integer type magic is required because the C++ standard is
// vague a about the equivalence of integral types for overloading. E.g. char is
// sometimes equivalent to signed char, sometimes unsigned char, sometimes
// neither. int8_t or uint8_t may or may not be equivalent to a char type.
// int64_t may or may not be equivalent to long long etc. C++ compilers are also
// allowed to add their own non-standard integer types like __int64, which may
// or may not be equivalent to any of the standard integer types.
//
// The solution is to use a fixed, standard set of integer types that are
// guaranteed to be distinct for overloading (see type_id_of) and to use template
// specialization to convert other integer types to a known integer type with the
// same sizeof and is_signed.
// Map arbitrary integral types to known integral types.
template<size_t SIZE, bool IS_SIGNED> struct integer_type;
template<> struct integer_type<1, true> { typedef int8_t type; };
template<> struct integer_type<2, true> { typedef int16_t type; };
template<> struct integer_type<4, true> { typedef int32_t type; };
template<> struct integer_type<8, true> { typedef int64_t type; };
template<> struct integer_type<1, false> { typedef uint8_t type; };
template<> struct integer_type<2, false> { typedef uint16_t type; };
template<> struct integer_type<4, false> { typedef uint32_t type; };
template<> struct integer_type<8, false> { typedef uint64_t type; };
// True if T is an integer type that does not have an explicit type_id.
template <class T> struct is_unknown_integer {
static const bool value = !has_type_id<T>::value && is_integral<T>::value;
};
template<class T, class = typename enable_if<is_unknown_integer<T>::value>::type>
struct known_integer : public integer_type<sizeof(T), is_signed<T>::value> {};
// Helper base for SFINAE templates.
struct sfinae {
typedef char yes;
typedef double no;
struct wildcard { wildcard(...); };
};
template <class From, class To> struct is_convertible : public sfinae {
static yes test(const To&);
static no test(...);
static const From& from;
// Windows compilers warn about data-loss caused by legal conversions. We
// can't use static_cast because that will cause a hard error instead of
// letting SFINAE overload resolution select the test(...) overload.
#ifdef _WIN32
#pragma warning( push )
#pragma warning( disable : 4244 )
#endif
static bool const value = sizeof(test(from)) == sizeof(yes);
#ifdef _WIN32
#pragma warning( pop )
#endif
};
} // internal
} // proton
#endif // PROTON_INTERNAL_TYPE_TRAITS_HPP
std
STL namespace.
proton::type_id
type_id
An identifier for AMQP types.
Definition: type_id.hpp:38
proton
Type traits for mapping between AMQP and C++ types.
Definition: annotation_key.hpp:28