We need a new regex standard besides POSIX BRE/ERE and ECMAScript

regexp.cpp

// ECMAScript regex
std::regex re_param(R"((\S+)\s+([\s\S]+))");

// vs.

// PCRE
pcrecpp::RE re_param(
    "(?# Match the annotation name)(\\S+)"
    "(?# Skip over whitespace)\\s+"
    "(?# Match the annotation description text)([\\s\\S]+)"
);