diff options
| -rw-r--r-- | server/lexer/details/parse.cpp | 53 |
1 files changed, 32 insertions, 21 deletions
diff --git a/server/lexer/details/parse.cpp b/server/lexer/details/parse.cpp index 25a77ce..efb3bdd 100644 --- a/server/lexer/details/parse.cpp +++ b/server/lexer/details/parse.cpp @@ -20,11 +20,12 @@ namespace math::server::lexer::details { namespace { -template <template<typename> typename MatchResultsT> +// This approach gives GCC on Travis an "internal compiler error": +//template <template <typename> class MatchResultsT> + +template <typename MatchResultsT> class RegexMatcher { public: - using MatchResults = MatchResultsT<std::string_view::const_iterator>; - virtual ~RegexMatcher() = default; virtual bool match_regex(const std::string_view& input) = 0; @@ -37,14 +38,14 @@ public: std::string to_str() const { return m_match[0].str(); } protected: - MatchResults m_match; + MatchResultsT m_match; }; -template <template<typename> typename MatchResultsT> +template <typename MatchResultsT> class RegexNumberMatcher : public RegexMatcher<MatchResultsT> { public: bool match(const std::string_view& input) { - if (!match_regex(input)) { + if (!this->match_regex(input)) { return false; } // If we have the numeric part of a number followed by 'e' and no @@ -52,7 +53,7 @@ public: // 1) that 'e' definitely belongs to this number token, // 2) the user forgot to type in the required digits. if (matched_e() && !matched_e_power()) { - throw LexerError{"exponent has no digits: " + to_str()}; + throw LexerError{"exponent has no digits: " + this->to_str()}; } return true; } @@ -64,12 +65,15 @@ protected: static constexpr std::string_view NUMBER_REGEX{R"REGEX(^(?:\d+(?:\.\d*)?|\.\d+)(e[+-]?(\d*))?)REGEX"}; private: - bool matched_e() const { return m_match[1].matched; } + bool matched_e() const { return this->m_match[1].matched; } - bool matched_e_power() const { return m_match[2].matched && m_match[2].length() != 0; } + bool matched_e_power() const { + return this->m_match[2].matched && this->m_match[2].length() != 0; + } }; -class StdNumberMatcher : public RegexNumberMatcher<std::match_results> { +class StdNumberMatcher + : public RegexNumberMatcher<std::match_results<std::string_view::const_iterator>> { public: bool match_regex(const std::string_view& input) override { return std::regex_search(input.cbegin(), input.cend(), m_match, get_regex()); @@ -85,7 +89,8 @@ private: } }; -class BoostNumberMatcher : public RegexNumberMatcher<boost::match_results> { +class BoostNumberMatcher + : public RegexNumberMatcher<boost::match_results<std::string_view::const_iterator>> { public: bool match_regex(const std::string_view& input) override { return boost::regex_search(input.cbegin(), input.cend(), m_match, get_regex()); @@ -101,8 +106,12 @@ private: } }; -template <template<typename> typename MatchResultsT> -std::optional<double> parse_number(const std::string_view& input, RegexNumberMatcher<MatchResultsT>&& matcher, std::string_view& token) { +template <typename MatchResultsT> +std::optional<double> parse_number( + const std::string_view& input, + RegexNumberMatcher<MatchResultsT>&& matcher, + std::string_view& token) { + if (!matcher.match(input)) { return {}; } @@ -117,16 +126,14 @@ std::optional<double> parse_number(const std::string_view& input, RegexNumberMat return {}; } -template <template<typename> typename MatchResultsT> +template <typename MatchResultsT> class RegexWhitespaceMatcher : public RegexMatcher<MatchResultsT> { protected: - // This is a hacky attempt to describe a C-like grammar for floating-point - // numbers using a regex (the tests seem to pass though). - // A proper NFA would be better, I guess. static constexpr std::string_view WS_REGEX{R"(^\s+)"}; }; -class StdWhitespaceMatcher : public RegexWhitespaceMatcher<std::match_results> { +class StdWhitespaceMatcher + : public RegexWhitespaceMatcher<std::match_results<std::string_view::const_iterator>> { public: bool match_regex(const std::string_view& input) override { return std::regex_search(input.cbegin(), input.cend(), m_match, get_regex()); @@ -140,7 +147,8 @@ private: } }; -class BoostWhitespaceMatcher : public RegexWhitespaceMatcher<boost::match_results> { +class BoostWhitespaceMatcher + : public RegexWhitespaceMatcher<boost::match_results<std::string_view::const_iterator>> { public: bool match_regex(const std::string_view& input) override { return boost::regex_search(input.cbegin(), input.cend(), m_match, get_regex()); @@ -154,8 +162,11 @@ private: } }; -template <template<typename> typename MatchResultsT> -std::string_view parse_whitespace(const std::string_view& input, RegexWhitespaceMatcher<MatchResultsT>&& matcher) { +template <typename MatchResultsT> +std::string_view parse_whitespace( + const std::string_view& input, + RegexWhitespaceMatcher<MatchResultsT>&& matcher) { + if (matcher.match_regex(input)) { return matcher.to_view(); } |