/***************************************************************************** Copyright (c) 2019, 2020 MariaDB Corporation. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA *****************************************************************************/ #pragma once #include #include namespace st_ { namespace detail { template struct remove_cv { typedef T type; }; template struct remove_cv { typedef T type; }; template struct remove_cv { typedef T type; }; template struct remove_cv { typedef T type; }; } // namespace detail template class span { public: typedef ElementType element_type; typedef typename detail::remove_cv::type value_type; typedef size_t size_type; typedef ptrdiff_t difference_type; typedef element_type *pointer; typedef const element_type *const_pointer; typedef element_type &reference; typedef const element_type &const_reference; typedef pointer iterator; typedef const_pointer const_iterator; typedef std::reverse_iterator reverse_iterator; span() : data_(NULL), size_(0) {} span(pointer ptr, size_type count) : data_(ptr), size_(count) {} span(pointer first, pointer last) : data_(first), size_(last - first) {} template span(element_type (&arr)[N]) : data_(arr), size_(N) {} template span(Container &cont) : data_(cont.data()), size_(cont.size()) { } template span(const Container &cont) : data_(cont.data()), size_(cont.size()) { } span(const span &other) : data_(other.data_), size_(other.size_) {} ~span() = default; span &operator=(const span &other) { data_= other.data(); size_= other.size(); return *this; } template span first() const { assert(!empty()); return span(data(), 1); } template span last() const { assert(!empty()); return span(data() + size() - 1, 1); } span first(size_type count) const { assert(!empty()); return span(data(), 1); } span last(size_type count) const { assert(!empty()); return span(data() + size() - 1, 1); } span subspan(size_type offset, size_type count) const { assert(!empty()); assert(size() >= offset + count); return span(data() + offset, count); } size_type size() const { return size_; } size_type size_bytes() const { return size() * sizeof(ElementType); } bool empty() const __attribute__((warn_unused_result)) { return size() == 0; } reference operator[](size_type idx) const { assert(size() > idx); return data()[idx]; } reference front() const { assert(!empty()); return data()[0]; } reference back() const { assert(!empty()); return data()[size() - 1]; } pointer data() const { return data_; } iterator begin() const { return data_; } iterator end() const { return data_ + size_; } reverse_iterator rbegin() const { return std::reverse_iterator(end()); } reverse_iterator rend() const { return std::reverse_iterator(begin()); } private: pointer data_; size_type size_; }; } // namespace st_