Merge pull request #860 from bogemic/std_iterator_conformance_cpp17

iter_impl template conformance with C++17
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Niels Lohmann 2017-12-08 07:55:47 +01:00 committed by GitHub
commit 0693945230
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@ -3631,7 +3631,7 @@ This class implements a both iterators (iterator and const_iterator) for the
iterators in version 3.0.0 (see https://github.com/nlohmann/json/issues/593)
*/
template<typename BasicJsonType>
class iter_impl : public std::iterator<std::bidirectional_iterator_tag, BasicJsonType>
class iter_impl
{
/// allow basic_json to access private members
friend iter_impl<typename std::conditional<std::is_const<BasicJsonType>::value, typename std::remove_const<BasicJsonType>::type, const BasicJsonType>::type>;
@ -3645,6 +3645,14 @@ class iter_impl : public std::iterator<std::bidirectional_iterator_tag, BasicJso
"iter_impl only accepts (const) basic_json");
public:
/// The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17.
/// The C++ Standard has never required user-defined iterators to derive from std::iterator.
/// A user-defined iterator should provide publicly accessible typedefs named
/// iterator_category, value_type, difference_type, pointer, and reference.
/// Note that value_type is required to be non-const, even for constant iterators.
using iterator_category = std::bidirectional_iterator_tag;
/// the type of the values when the iterator is dereferenced
using value_type = typename BasicJsonType::value_type;
/// a type to represent differences between iterators