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Diffstat (limited to 'libraries/toml11/include')
23 files changed, 10419 insertions, 0 deletions
diff --git a/libraries/toml11/include/toml.hpp b/libraries/toml11/include/toml.hpp new file mode 100644 index 00000000..9ed1216e --- /dev/null +++ b/libraries/toml11/include/toml.hpp @@ -0,0 +1,46 @@ +/* + * The MIT License (MIT) + * + * Copyright (c) 2017 Toru Niina + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#ifndef TOML_FOR_MODERN_CPP +#define TOML_FOR_MODERN_CPP + +#ifndef __cplusplus +# error "__cplusplus is not defined" +#endif + +#if __cplusplus < 201103L && _MSC_VER < 1900 +# error "toml11 requires C++11 or later." +#endif + +#define TOML11_VERSION_MAJOR 3 +#define TOML11_VERSION_MINOR 6 +#define TOML11_VERSION_PATCH 1 + +#include "toml/parser.hpp" +#include "toml/literal.hpp" +#include "toml/serializer.hpp" +#include "toml/get.hpp" +#include "toml/macros.hpp" + +#endif// TOML_FOR_MODERN_CPP diff --git a/libraries/toml11/include/toml/color.hpp b/libraries/toml11/include/toml/color.hpp new file mode 100644 index 00000000..4cb572cb --- /dev/null +++ b/libraries/toml11/include/toml/color.hpp @@ -0,0 +1,64 @@ +#ifndef TOML11_COLOR_HPP +#define TOML11_COLOR_HPP +#include <cstdint> +#include <ostream> + +#ifdef TOML11_COLORIZE_ERROR_MESSAGE +#define TOML11_ERROR_MESSAGE_COLORIZED true +#else +#define TOML11_ERROR_MESSAGE_COLORIZED false +#endif + +namespace toml +{ + +// put ANSI escape sequence to ostream +namespace color_ansi +{ +namespace detail +{ +inline int colorize_index() +{ + static const int index = std::ios_base::xalloc(); + return index; +} +} // detail + +inline std::ostream& colorize(std::ostream& os) +{ + // by default, it is zero. + os.iword(detail::colorize_index()) = 1; + return os; +} +inline std::ostream& nocolorize(std::ostream& os) +{ + os.iword(detail::colorize_index()) = 0; + return os; +} +inline std::ostream& reset (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[00m";} return os;} +inline std::ostream& bold (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[01m";} return os;} +inline std::ostream& grey (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[30m";} return os;} +inline std::ostream& red (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[31m";} return os;} +inline std::ostream& green (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[32m";} return os;} +inline std::ostream& yellow (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[33m";} return os;} +inline std::ostream& blue (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[34m";} return os;} +inline std::ostream& magenta(std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[35m";} return os;} +inline std::ostream& cyan (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[36m";} return os;} +inline std::ostream& white (std::ostream& os) +{if(os.iword(detail::colorize_index()) == 1) {os << "\033[37m";} return os;} +} // color_ansi + +// ANSI escape sequence is the only and default colorization method currently +namespace color = color_ansi; + +} // toml +#endif// TOML11_COLOR_HPP diff --git a/libraries/toml11/include/toml/combinator.hpp b/libraries/toml11/include/toml/combinator.hpp new file mode 100644 index 00000000..e250188f --- /dev/null +++ b/libraries/toml11/include/toml/combinator.hpp @@ -0,0 +1,306 @@ +// Copyright Toru Niina 2017. +// Distributed under the MIT License. +#ifndef TOML11_COMBINATOR_HPP +#define TOML11_COMBINATOR_HPP +#include <cassert> +#include <cctype> +#include <cstdio> + +#include <array> +#include <iomanip> +#include <iterator> +#include <limits> +#include <type_traits> + +#include "region.hpp" +#include "result.hpp" +#include "traits.hpp" +#include "utility.hpp" + +// they scans characters and returns region if it matches to the condition. +// when they fail, it does not change the location. +// in lexer.hpp, these are used. + +namespace toml +{ +namespace detail +{ + +// to output character as an error message. +inline std::string show_char(const char c) +{ + // It supress an error that occurs only in Debug mode of MSVC++ on Windows. + // I'm not completely sure but they check the value of char to be in the + // range [0, 256) and some of the COMPLETELY VALID utf-8 character sometimes + // has negative value (if char has sign). So here it re-interprets c as + // unsigned char through pointer. In general, converting pointer to a + // pointer that has different type cause UB, but `(signed|unsigned)?char` + // are one of the exceptions. Converting pointer only to char and std::byte + // (c++17) are valid. + if(std::isgraph(*reinterpret_cast<unsigned char const*>(std::addressof(c)))) + { + return std::string(1, c); + } + else + { + std::array<char, 5> buf; + buf.fill('\0'); + const auto r = std::snprintf( + buf.data(), buf.size(), "0x%02x", static_cast<int>(c) & 0xFF); + (void) r; // Unused variable warning + assert(r == static_cast<int>(buf.size()) - 1); + return std::string(buf.data()); + } +} + +template<char C> +struct character +{ + static constexpr char target = C; + + static result<region, none_t> + invoke(location& loc) + { + if(loc.iter() == loc.end()) {return none();} + const auto first = loc.iter(); + + const char c = *(loc.iter()); + if(c != target) + { + return none(); + } + loc.advance(); // update location + + return ok(region(loc, first, loc.iter())); + } +}; +template<char C> +constexpr char character<C>::target; + +// closed interval [Low, Up]. both Low and Up are included. +template<char Low, char Up> +struct in_range +{ + // assuming ascii part of UTF-8... + static_assert(Low <= Up, "lower bound should be less than upper bound."); + + static constexpr char upper = Up; + static constexpr char lower = Low; + + static result<region, none_t> + invoke(location& loc) + { + if(loc.iter() == loc.end()) {return none();} + const auto first = loc.iter(); + + const char c = *(loc.iter()); + if(c < lower || upper < c) + { + return none(); + } + + loc.advance(); + return ok(region(loc, first, loc.iter())); + } +}; +template<char L, char U> constexpr char in_range<L, U>::upper; +template<char L, char U> constexpr char in_range<L, U>::lower; + +// keep iterator if `Combinator` matches. otherwise, increment `iter` by 1 char. +// for detecting invalid characters, like control sequences in toml string. +template<typename Combinator> +struct exclude +{ + static result<region, none_t> + invoke(location& loc) + { + if(loc.iter() == loc.end()) {return none();} + auto first = loc.iter(); + + auto rslt = Combinator::invoke(loc); + if(rslt.is_ok()) + { + loc.reset(first); + return none(); + } + loc.reset(std::next(first)); // XXX maybe loc.advance() is okay but... + return ok(region(loc, first, loc.iter())); + } +}; + +// increment `iter`, if matches. otherwise, just return empty string. +template<typename Combinator> +struct maybe +{ + static result<region, none_t> + invoke(location& loc) + { + const auto rslt = Combinator::invoke(loc); + if(rslt.is_ok()) + { + return rslt; + } + return ok(region(loc)); + } +}; + +template<typename ... Ts> +struct sequence; + +template<typename Head, typename ... Tail> +struct sequence<Head, Tail...> +{ + static result<region, none_t> + invoke(location& loc) + { + const auto first = loc.iter(); + const auto rslt = Head::invoke(loc); + if(rslt.is_err()) + { + loc.reset(first); + return none(); + } + return sequence<Tail...>::invoke(loc, std::move(rslt.unwrap()), first); + } + + // called from the above function only, recursively. + template<typename Iterator> + static result<region, none_t> + invoke(location& loc, region reg, Iterator first) + { + const auto rslt = Head::invoke(loc); + if(rslt.is_err()) + { + loc.reset(first); + return none(); + } + reg += rslt.unwrap(); // concat regions + return sequence<Tail...>::invoke(loc, std::move(reg), first); + } +}; + +template<typename Head> +struct sequence<Head> +{ + // would be called from sequence<T ...>::invoke only. + template<typename Iterator> + static result<region, none_t> + invoke(location& loc, region reg, Iterator first) + { + const auto rslt = Head::invoke(loc); + if(rslt.is_err()) + { + loc.reset(first); + return none(); + } + reg += rslt.unwrap(); // concat regions + return ok(reg); + } +}; + +template<typename ... Ts> +struct either; + +template<typename Head, typename ... Tail> +struct either<Head, Tail...> +{ + static result<region, none_t> + invoke(location& loc) + { + const auto rslt = Head::invoke(loc); + if(rslt.is_ok()) {return rslt;} + return either<Tail...>::invoke(loc); + } +}; +template<typename Head> +struct either<Head> +{ + static result<region, none_t> + invoke(location& loc) + { + return Head::invoke(loc); + } +}; + +template<typename T, typename N> +struct repeat; + +template<std::size_t N> struct exactly{}; +template<std::size_t N> struct at_least{}; +struct unlimited{}; + +template<typename T, std::size_t N> +struct repeat<T, exactly<N>> +{ + static result<region, none_t> + invoke(location& loc) + { + region retval(loc); + const auto first = loc.iter(); + for(std::size_t i=0; i<N; ++i) + { + auto rslt = T::invoke(loc); + if(rslt.is_err()) + { + loc.reset(first); + return none(); + } + retval += rslt.unwrap(); + } + return ok(std::move(retval)); + } +}; + +template<typename T, std::size_t N> +struct repeat<T, at_least<N>> +{ + static result<region, none_t> + invoke(location& loc) + { + region retval(loc); + + const auto first = loc.iter(); + for(std::size_t i=0; i<N; ++i) + { + auto rslt = T::invoke(loc); + if(rslt.is_err()) + { + loc.reset(first); + return none(); + } + retval += rslt.unwrap(); + } + while(true) + { + auto rslt = T::invoke(loc); + if(rslt.is_err()) + { + return ok(std::move(retval)); + } + retval += rslt.unwrap(); + } + } +}; + +template<typename T> +struct repeat<T, unlimited> +{ + static result<region, none_t> + invoke(location& loc) + { + region retval(loc); + while(true) + { + auto rslt = T::invoke(loc); + if(rslt.is_err()) + { + return ok(std::move(retval)); + } + retval += rslt.unwrap(); + } + } +}; + +} // detail +} // toml +#endif// TOML11_COMBINATOR_HPP diff --git a/libraries/toml11/include/toml/comments.hpp b/libraries/toml11/include/toml/comments.hpp new file mode 100644 index 00000000..92fc8e13 --- /dev/null +++ b/libraries/toml11/include/toml/comments.hpp @@ -0,0 +1,466 @@ +// Copyright Toru Niina 2019. +// Distributed under the MIT License. +#ifndef TOML11_COMMENTS_HPP +#define TOML11_COMMENTS_HPP +#include <initializer_list> +#include <iterator> +#include <stdexcept> +#include <string> +#include <type_traits> +#include <utility> +#include <vector> + +// This file provides mainly two classes, `preserve_comments` and `discard_comments`. +// Those two are a container that have the same interface as `std::vector<std::string>` +// but bahaves in the opposite way. `preserve_comments` is just the same as +// `std::vector<std::string>` and each `std::string` corresponds to a comment line. +// Conversely, `discard_comments` discards all the strings and ignores everything +// assigned in it. `discard_comments` is always empty and you will encounter an +// error whenever you access to the element. +namespace toml +{ +struct discard_comments; // forward decl + +// use it in the following way +// +// const toml::basic_value<toml::preserve_comments> data = +// toml::parse<toml::preserve_comments>("example.toml"); +// +// the interface is almost the same as std::vector<std::string>. +struct preserve_comments +{ + // `container_type` is not provided in discard_comments. + // do not use this inner-type in a generic code. + using container_type = std::vector<std::string>; + + using size_type = container_type::size_type; + using difference_type = container_type::difference_type; + using value_type = container_type::value_type; + using reference = container_type::reference; + using const_reference = container_type::const_reference; + using pointer = container_type::pointer; + using const_pointer = container_type::const_pointer; + using iterator = container_type::iterator; + using const_iterator = container_type::const_iterator; + using reverse_iterator = container_type::reverse_iterator; + using const_reverse_iterator = container_type::const_reverse_iterator; + + preserve_comments() = default; + ~preserve_comments() = default; + preserve_comments(preserve_comments const&) = default; + preserve_comments(preserve_comments &&) = default; + preserve_comments& operator=(preserve_comments const&) = default; + preserve_comments& operator=(preserve_comments &&) = default; + + explicit preserve_comments(const std::vector<std::string>& c): comments(c){} + explicit preserve_comments(std::vector<std::string>&& c) + : comments(std::move(c)) + {} + preserve_comments& operator=(const std::vector<std::string>& c) + { + comments = c; + return *this; + } + preserve_comments& operator=(std::vector<std::string>&& c) + { + comments = std::move(c); + return *this; + } + + explicit preserve_comments(const discard_comments&) {} + + explicit preserve_comments(size_type n): comments(n) {} + preserve_comments(size_type n, const std::string& x): comments(n, x) {} + preserve_comments(std::initializer_list<std::string> x): comments(x) {} + template<typename InputIterator> + preserve_comments(InputIterator first, InputIterator last) + : comments(first, last) + {} + + template<typename InputIterator> + void assign(InputIterator first, InputIterator last) {comments.assign(first, last);} + void assign(std::initializer_list<std::string> ini) {comments.assign(ini);} + void assign(size_type n, const std::string& val) {comments.assign(n, val);} + + // Related to the issue #97. + // + // It is known that `std::vector::insert` and `std::vector::erase` in + // the standard library implementation included in GCC 4.8.5 takes + // `std::vector::iterator` instead of `std::vector::const_iterator`. + // Because of the const-correctness, we cannot convert a `const_iterator` to + // an `iterator`. It causes compilation error in GCC 4.8.5. +#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__) && !defined(__clang__) +# if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) <= 40805 +# define TOML11_WORKAROUND_GCC_4_8_X_STANDARD_LIBRARY_IMPLEMENTATION +# endif +#endif + +#ifdef TOML11_WORKAROUND_GCC_4_8_X_STANDARD_LIBRARY_IMPLEMENTATION + iterator insert(iterator p, const std::string& x) + { + return comments.insert(p, x); + } + iterator insert(iterator p, std::string&& x) + { + return comments.insert(p, std::move(x)); + } + void insert(iterator p, size_type n, const std::string& x) + { + return comments.insert(p, n, x); + } + template<typename InputIterator> + void insert(iterator p, InputIterator first, InputIterator last) + { + return comments.insert(p, first, last); + } + void insert(iterator p, std::initializer_list<std::string> ini) + { + return comments.insert(p, ini); + } + + template<typename ... Ts> + iterator emplace(iterator p, Ts&& ... args) + { + return comments.emplace(p, std::forward<Ts>(args)...); + } + + iterator erase(iterator pos) {return comments.erase(pos);} + iterator erase(iterator first, iterator last) + { + return comments.erase(first, last); + } +#else + iterator insert(const_iterator p, const std::string& x) + { + return comments.insert(p, x); + } + iterator insert(const_iterator p, std::string&& x) + { + return comments.insert(p, std::move(x)); + } + iterator insert(const_iterator p, size_type n, const std::string& x) + { + return comments.insert(p, n, x); + } + template<typename InputIterator> + iterator insert(const_iterator p, InputIterator first, InputIterator last) + { + return comments.insert(p, first, last); + } + iterator insert(const_iterator p, std::initializer_list<std::string> ini) + { + return comments.insert(p, ini); + } + + template<typename ... Ts> + iterator emplace(const_iterator p, Ts&& ... args) + { + return comments.emplace(p, std::forward<Ts>(args)...); + } + + iterator erase(const_iterator pos) {return comments.erase(pos);} + iterator erase(const_iterator first, const_iterator last) + { + return comments.erase(first, last); + } +#endif + + void swap(preserve_comments& other) {comments.swap(other.comments);} + + void push_back(const std::string& v) {comments.push_back(v);} + void push_back(std::string&& v) {comments.push_back(std::move(v));} + void pop_back() {comments.pop_back();} + + template<typename ... Ts> + void emplace_back(Ts&& ... args) {comments.emplace_back(std::forward<Ts>(args)...);} + + void clear() {comments.clear();} + + size_type size() const noexcept {return comments.size();} + size_type max_size() const noexcept {return comments.max_size();} + size_type capacity() const noexcept {return comments.capacity();} + bool empty() const noexcept {return comments.empty();} + + void reserve(size_type n) {comments.reserve(n);} + void resize(size_type n) {comments.resize(n);} + void resize(size_type n, const std::string& c) {comments.resize(n, c);} + void shrink_to_fit() {comments.shrink_to_fit();} + + reference operator[](const size_type n) noexcept {return comments[n];} + const_reference operator[](const size_type n) const noexcept {return comments[n];} + reference at(const size_type n) {return comments.at(n);} + const_reference at(const size_type n) const {return comments.at(n);} + reference front() noexcept {return comments.front();} + const_reference front() const noexcept {return comments.front();} + reference back() noexcept {return comments.back();} + const_reference back() const noexcept {return comments.back();} + + pointer data() noexcept {return comments.data();} + const_pointer data() const noexcept {return comments.data();} + + iterator begin() noexcept {return comments.begin();} + iterator end() noexcept {return comments.end();} + const_iterator begin() const noexcept {return comments.begin();} + const_iterator end() const noexcept {return comments.end();} + const_iterator cbegin() const noexcept {return comments.cbegin();} + const_iterator cend() const noexcept {return comments.cend();} + + reverse_iterator rbegin() noexcept {return comments.rbegin();} + reverse_iterator rend() noexcept {return comments.rend();} + const_reverse_iterator rbegin() const noexcept {return comments.rbegin();} + const_reverse_iterator rend() const noexcept {return comments.rend();} + const_reverse_iterator crbegin() const noexcept {return comments.crbegin();} + const_reverse_iterator crend() const noexcept {return comments.crend();} + + friend bool operator==(const preserve_comments&, const preserve_comments&); + friend bool operator!=(const preserve_comments&, const preserve_comments&); + friend bool operator< (const preserve_comments&, const preserve_comments&); + friend bool operator<=(const preserve_comments&, const preserve_comments&); + friend bool operator> (const preserve_comments&, const preserve_comments&); + friend bool operator>=(const preserve_comments&, const preserve_comments&); + + friend void swap(preserve_comments&, std::vector<std::string>&); + friend void swap(std::vector<std::string>&, preserve_comments&); + + private: + + container_type comments; +}; + +inline bool operator==(const preserve_comments& lhs, const preserve_comments& rhs) {return lhs.comments == rhs.comments;} +inline bool operator!=(const preserve_comments& lhs, const preserve_comments& rhs) {return lhs.comments != rhs.comments;} +inline bool operator< (const preserve_comments& lhs, const preserve_comments& rhs) {return lhs.comments < rhs.comments;} +inline bool operator<=(const preserve_comments& lhs, const preserve_comments& rhs) {return lhs.comments <= rhs.comments;} +inline bool operator> (const preserve_comments& lhs, const preserve_comments& rhs) {return lhs.comments > rhs.comments;} +inline bool operator>=(const preserve_comments& lhs, const preserve_comments& rhs) {return lhs.comments >= rhs.comments;} + +inline void swap(preserve_comments& lhs, preserve_comments& rhs) +{ + lhs.swap(rhs); + return; +} +inline void swap(preserve_comments& lhs, std::vector<std::string>& rhs) +{ + lhs.comments.swap(rhs); + return; +} +inline void swap(std::vector<std::string>& lhs, preserve_comments& rhs) +{ + lhs.swap(rhs.comments); + return; +} + +template<typename charT, typename traits> +std::basic_ostream<charT, traits>& +operator<<(std::basic_ostream<charT, traits>& os, const preserve_comments& com) +{ + for(const auto& c : com) + { + os << '#' << c << '\n'; + } + return os; +} + +namespace detail +{ + +// To provide the same interface with `preserve_comments`, `discard_comments` +// should have an iterator. But it does not contain anything, so we need to +// add an iterator that points nothing. +// +// It always points null, so DO NOT unwrap this iterator. It always crashes +// your program. +template<typename T, bool is_const> +struct empty_iterator +{ + using value_type = T; + using reference_type = typename std::conditional<is_const, T const&, T&>::type; + using pointer_type = typename std::conditional<is_const, T const*, T*>::type; + using difference_type = std::ptrdiff_t; + using iterator_category = std::random_access_iterator_tag; + + empty_iterator() = default; + ~empty_iterator() = default; + empty_iterator(empty_iterator const&) = default; + empty_iterator(empty_iterator &&) = default; + empty_iterator& operator=(empty_iterator const&) = default; + empty_iterator& operator=(empty_iterator &&) = default; + + // DO NOT call these operators. + reference_type operator*() const noexcept {std::terminate();} + pointer_type operator->() const noexcept {return nullptr;} + reference_type operator[](difference_type) const noexcept {return this->operator*();} + + // These operators do nothing. + empty_iterator& operator++() noexcept {return *this;} + empty_iterator operator++(int) noexcept {return *this;} + empty_iterator& operator--() noexcept {return *this;} + empty_iterator operator--(int) noexcept {return *this;} + + empty_iterator& operator+=(difference_type) noexcept {return *this;} + empty_iterator& operator-=(difference_type) noexcept {return *this;} + + empty_iterator operator+(difference_type) const noexcept {return *this;} + empty_iterator operator-(difference_type) const noexcept {return *this;} +}; + +template<typename T, bool C> +bool operator==(const empty_iterator<T, C>&, const empty_iterator<T, C>&) noexcept {return true;} +template<typename T, bool C> +bool operator!=(const empty_iterator<T, C>&, const empty_iterator<T, C>&) noexcept {return false;} +template<typename T, bool C> +bool operator< (const empty_iterator<T, C>&, const empty_iterator<T, C>&) noexcept {return false;} +template<typename T, bool C> +bool operator<=(const empty_iterator<T, C>&, const empty_iterator<T, C>&) noexcept {return true;} +template<typename T, bool C> +bool operator> (const empty_iterator<T, C>&, const empty_iterator<T, C>&) noexcept {return false;} +template<typename T, bool C> +bool operator>=(const empty_iterator<T, C>&, const empty_iterator<T, C>&) noexcept {return true;} + +template<typename T, bool C> +typename empty_iterator<T, C>::difference_type +operator-(const empty_iterator<T, C>&, const empty_iterator<T, C>&) noexcept {return 0;} + +template<typename T, bool C> +empty_iterator<T, C> +operator+(typename empty_iterator<T, C>::difference_type, const empty_iterator<T, C>& rhs) noexcept {return rhs;} +template<typename T, bool C> +empty_iterator<T, C> +operator+(const empty_iterator<T, C>& lhs, typename empty_iterator<T, C>::difference_type) noexcept {return lhs;} + +} // detail + +// The default comment type. It discards all the comments. It requires only one +// byte to contain, so the memory footprint is smaller than preserve_comments. +// +// It just ignores `push_back`, `insert`, `erase`, and any other modifications. +// IT always returns size() == 0, the iterator taken by `begin()` is always the +// same as that of `end()`, and accessing through `operator[]` or iterators +// always causes a segmentation fault. DO NOT access to the element of this. +// +// Why this is chose as the default type is because the last version (2.x.y) +// does not contain any comments in a value. To minimize the impact on the +// efficiency, this is choosed as a default. +// +// To reduce the memory footprint, later we can try empty base optimization (EBO). +struct discard_comments +{ + using size_type = std::size_t; + using difference_type = std::ptrdiff_t; + using value_type = std::string; + using reference = std::string&; + using const_reference = std::string const&; + using pointer = std::string*; + using const_pointer = std::string const*; + using iterator = detail::empty_iterator<std::string, false>; + using const_iterator = detail::empty_iterator<std::string, true>; + using reverse_iterator = detail::empty_iterator<std::string, false>; + using const_reverse_iterator = detail::empty_iterator<std::string, true>; + + discard_comments() = default; + ~discard_comments() = default; + discard_comments(discard_comments const&) = default; + discard_comments(discard_comments &&) = default; + discard_comments& operator=(discard_comments const&) = default; + discard_comments& operator=(discard_comments &&) = default; + + explicit discard_comments(const std::vector<std::string>&) noexcept {} + explicit discard_comments(std::vector<std::string>&&) noexcept {} + discard_comments& operator=(const std::vector<std::string>&) noexcept {return *this;} + discard_comments& operator=(std::vector<std::string>&&) noexcept {return *this;} + + explicit discard_comments(const preserve_comments&) noexcept {} + + explicit discard_comments(size_type) noexcept {} + discard_comments(size_type, const std::string&) noexcept {} + discard_comments(std::initializer_list<std::string>) noexcept {} + template<typename InputIterator> + discard_comments(InputIterator, InputIterator) noexcept {} + + template<typename InputIterator> + void assign(InputIterator, InputIterator) noexcept {} + void assign(std::initializer_list<std::string>) noexcept {} + void assign(size_type, const std::string&) noexcept {} + + iterator insert(const_iterator, const std::string&) {return iterator{};} + iterator insert(const_iterator, std::string&&) {return iterator{};} + iterator insert(const_iterator, size_type, const std::string&) |