Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include <type_traits>
       7             : 
       8             : namespace tt {
       9             : /// @{
      10             : /// \ingroup TypeTraitsGroup
      11             : /// \brief Check if type T has a begin() and end() function
      12             : ///
      13             : /// \details
      14             : /// Given a type `T` inherits from std::true_type if `T` has member functions
      15             : /// `begin()` and `end()`, otherwise inherits from std::false_type
      16             : ///
      17             : /// \usage
      18             : /// For any type `T`
      19             : /// \code
      20             : /// using result = tt::is_iterable<T>;
      21             : /// \endcode
      22             : ///
      23             : /// \metareturns
      24             : /// std::bool_constant
      25             : ///
      26             : /// \semantics
      27             : /// If `T` has member function `begin()` and `end()` then
      28             : /// \code
      29             : /// typename result::type = std::true_type;
      30             : /// \endcode
      31             : /// otherwise
      32             : /// \code
      33             : /// typename result::type = std::false_type;
      34             : /// \endcode
      35             : ///
      36             : /// \example
      37             : /// \snippet Test_IsIterable.cpp is_iterable_example
      38             : /// \tparam T the type to check
      39             : template <typename T, typename = std::void_t<>>
      40           1 : struct is_iterable : std::false_type {};
      41             : 
      42             : /// \cond HIDDEN_SYMBOLS
      43             : template <typename T>
      44             : struct is_iterable<T, std::void_t<decltype(std::declval<T>().begin(),
      45             :                                            std::declval<T>().end())>>
      46             :     : std::true_type {};
      47             : /// \endcond
      48             : 
      49             : /// \see is_iterable
      50             : template <typename T>
      51           1 : constexpr bool is_iterable_v = is_iterable<T>::value;
      52             : 
      53             : /// \see is_iterable
      54             : template <typename T>
      55           1 : using is_iterable_t = typename is_iterable<T>::type;
      56             : /// @}
      57             : }  // namespace tt