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diff --git a/include/jsoncons/detail/span.hpp b/include/jsoncons/detail/span.hpp
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+++ b/include/jsoncons/detail/span.hpp
@@ -0,0 +1,188 @@
+#ifndef JSONCONS_DETAIL_SPAN_HPP
+#define JSONCONS_DETAIL_SPAN_HPP
+
+#include <utility> // std::swap
+#include <memory> // std::addressof
+#include <type_traits> // std::enable_if, std::true_type, std::false_type
+#include <jsoncons/config/compiler_support.hpp>
+#include <jsoncons/more_type_traits.hpp>
+#include <iterator>
+#include <limits>
+
+namespace jsoncons
+{
+namespace detail
+{
+    constexpr std::size_t dynamic_extent = (std::numeric_limits<std::size_t>::max)();
+
+    template< class T, std::size_t Extent = dynamic_extent>
+    class span;
+
+    template<class T>
+    struct is_span : std::false_type{};
+
+    template< class T>
+    struct is_span<span<T>> : std::true_type{};
+
+    template<
+        class T,
+        std::size_t Extent
+    > class span
+    {
+    public:
+        using element_type = T;
+        using value_type = typename std::remove_volatile<typename std::remove_const<T>::type>::type;
+        using size_type = std::size_t;
+        using difference_type = std::ptrdiff_t;
+        using pointer = T*;
+        using const_pointer = const T*;
+        using reference = T&;
+        using const_reference = const T&;
+        using iterator = pointer;
+        using const_iterator = const_pointer;
+        using reverse_iterator = std::reverse_iterator<iterator>;
+        using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+    private:
+        pointer data_;
+        size_type size_;
+    public:
+        static constexpr std::size_t extent = Extent;
+
+        constexpr span() noexcept
+            : data_(nullptr), size_(0)
+        {
+        }
+        constexpr span(pointer data, size_type size)
+            : data_(data), size_(size)
+        {
+        }
+
+        template <typename C>
+        constexpr span(C& c,
+                       typename std::enable_if<!is_span<C>::value && !type_traits::is_std_array<C>::value && type_traits::is_compatible_element<C,element_type>::value && type_traits::has_data_and_size<C>::value>::type* = 0)
+            : data_(c.data()), size_(c.size())
+        {
+        }
+
+        template <std::size_t N>
+        span(element_type (&arr)[N]) noexcept
+            : data_(std::addressof(arr[0])), size_(N)
+        {
+        }
+
+        template <std::size_t N>
+        span(std::array<value_type, N>& arr,
+             typename std::enable_if<(extent == dynamic_extent || extent == N)>::type* = 0) noexcept
+            : data_(arr.data()), size_(arr.size())
+        {
+        }
+
+        template <std::size_t N>
+        span(const std::array<value_type, N>& arr,
+             typename std::enable_if<(extent == dynamic_extent || extent == N)>::type* = 0) noexcept
+            : data_(arr.data()), size_(arr.size())
+        {
+        }
+
+        template <typename C>
+        constexpr span(const C& c,
+                       typename std::enable_if<!is_span<C>::value && !type_traits::is_std_array<C>::value && type_traits::is_compatible_element<C,element_type>::value && type_traits::has_data_and_size<C>::value>::type* = 0)
+            : data_(c.data()), size_(c.size())
+        {
+        }
+
+        template <class U, std::size_t N>
+        constexpr span(const span<U, N>& s,
+                       typename std::enable_if<(N == dynamic_extent || N == extent) && std::is_convertible<U(*)[], element_type(*)[]>::value>::type* = 0) noexcept
+            : data_(s.data()), size_(s.size())
+        {
+        }
+
+        constexpr span(const span& other) noexcept = default;
+
+        span& operator=( const span& other ) noexcept = default;
+
+        constexpr pointer data() const noexcept
+        {
+            return data_;
+        }
+
+        constexpr size_type size() const noexcept
+        {
+            return size_;
+        }
+
+         constexpr bool empty() const noexcept 
+        { 
+            return size_ == 0; 
+        }
+
+         constexpr reference operator[](size_type index) const
+         {
+             return data_[index];
+         }
+
+        // iterator support 
+        const_iterator begin() const noexcept
+        {
+            return data_;
+        }
+        const_iterator end() const noexcept
+        {
+            return data_ + size_;
+        }
+        const_iterator cbegin() const noexcept 
+        { 
+            return data_; 
+        }
+        const_iterator cend() const noexcept 
+        { 
+            return data_ + size_; 
+        }
+        const_reverse_iterator rbegin() const noexcept 
+        { 
+            return const_reverse_iterator(end()); 
+        }
+        const_reverse_iterator rend() const noexcept 
+        { 
+            return const_reverse_iterator(begin()); 
+        }
+        const_reverse_iterator crbegin() const noexcept 
+        { 
+            return const_reverse_iterator(end()); 
+        }
+        const_reverse_iterator crend() const noexcept 
+        { 
+            return const_reverse_iterator(begin()); 
+        }
+
+        span<element_type, dynamic_extent>
+        first(std::size_t count) const
+        {
+            JSONCONS_ASSERT(count <= size());
+
+            return span< element_type, dynamic_extent >( data(), count );
+        }
+
+        span<element_type, dynamic_extent>
+        last(std::size_t count) const
+        {
+            JSONCONS_ASSERT(count <= size());
+
+            return span<element_type, dynamic_extent>(data() + ( size() - count ), count);
+        }
+
+        span<element_type, dynamic_extent>
+        subspan(std::size_t offset, std::size_t count = dynamic_extent) const
+        {
+            //JSONCONS_ASSERT((offset <= size() && (count == dynamic_extent || (offset + count <= size()))));
+
+            return span<element_type, dynamic_extent>(
+                data() + offset, count == dynamic_extent ? size() - offset : count );
+        }
+    };
+
+} // namespace detail
+} // namespace jsoncons
+
+#endif