74 lines
1.1 KiB
C++
74 lines
1.1 KiB
C++
#pragma once
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#include <iterator>
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template <typename I>
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class null_sentinel_iterator
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{
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public:
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using iterator_category = std::forward_iterator_tag;
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using value_type = I;
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using difference_type = std::ptrdiff_t;
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using pointer = I *;
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using reference = I &;
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null_sentinel_iterator() = default;
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null_sentinel_iterator(const pointer i) :
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p(i)
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{
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}
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pointer get() const
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{
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return p;
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}
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value_type operator*() const
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{
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return *p;
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}
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reference operator*()
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{
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return *p;
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}
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null_sentinel_iterator &operator++()
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{
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++p;
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return *this;
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}
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bool operator==(null_sentinel_iterator rhs) const
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{
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if (rhs.p)
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return p == rhs.p;
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if (!p)
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/* Should never happen */
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return true;
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return !**this;
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}
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private:
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pointer p = nullptr;
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};
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template <typename I>
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class null_sentinel_array
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{
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typedef null_sentinel_iterator<I> iterator;
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I *b;
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public:
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null_sentinel_array(I *i) :
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b(i)
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{
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}
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iterator begin() const
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{
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return b;
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}
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iterator end() const
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{
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return {};
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}
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};
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template <typename I>
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static inline null_sentinel_array<I> make_null_sentinel_array(I *i)
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{
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return i;
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}
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