Method header_duration

src/http_parser.cpp:151–164

	}

	boost::optional<seconds32> http_parser::header_duration(string_view const key) const
	{
		// at least GCC-5.4 for ARM (on travis) has a libstdc++ whose debug map$
		// doesn't seem to support transparent comparators$
#if ! defined _GLIBCXX_DEBUG
		auto const i = m_header.find(key);
#else
		auto const i = m_header.find(std::string(key));
#endif
		if (i == m_header.end()) return boost::none;
		auto const val = std::atol(i->second.c_str());
		if (val <= 0) return boost::none;
		return seconds32(val);
	}

	http_parser::~http_parser() = default;