type traits, C++ (vc++)

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#include <iostream>
#include <type_traits>
#include <iterator>

namespace detail
{
    template < typename T > struct is_sequence
    {
        template < typename U >
        static char test( U&&, decltype( std::begin( std::declval<U>() ) )* = 0 ) ;

using two_chars = char[2] ; static two_chars& test(...) ;

static constexpr bool value = sizeof( test( std::declval<T>() ) ) == 1 ;
    };

template < typename T > struct is_associative
    {
        template < typename U >
        static char test( U&&, typename U::key_type* = 0 ) ;

using two_chars = char[2] ; static two_chars& test(...) ;

static constexpr bool value = sizeof( test( std::declval<T>() ) ) == 1 ;
    };
}

template < typename T > struct is_sequence :
    std::conditional< detail::is_sequence<T>::value || std::is_array<T>::value,
                      std::true_type, std::false_type >::type {};

template < typename T > struct is_associative_sequence :
    std::conditional< detail::is_sequence<T>::value && detail::is_associative<T>::value,
                      std::true_type, std::false_type >::type {};

#include <vector>
#include <array>
#include <vector>
#include <map>
#include <unordered_set>

int main()
{
    using c_array = int[50] ;
    using array = std::array<int,50> ;
    using vector = std::vector<int> ;
    using map = std::map<int,int> ;
    using set = std::unordered_set<int> ;

std::cout << std::boolalpha

<< "      c array: " << is_sequence<c_array>::value << ' ' // true
              << is_associative_sequence<c_array>::value << '\n' // false

<< "    std array: " << is_sequence<array>::value << ' ' // true
              << is_associative_sequence<array>::value << '\n' // false

<< "       vector: " << is_sequence<vector>::value << ' ' // true
              << is_associative_sequence<vector>::value << '\n' // false

<< "          map: " << is_sequence<map>::value << ' ' // true
              << is_associative_sequence<map>::value << '\n' // true

<< "unordered_set: " << is_sequence<set>::value << ' ' // true
              << is_associative_sequence<set>::value << '\n' ; // true
}

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Compilation time: 1,82 sec, absolute running time: 0,33 sec, absolute service time: 2,17 sec