Function is_word_char

common/grammar-parser.cpp:49–51

    }

    static bool is_word_char(char c) {
        return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || c == '-' || ('0' <= c && c <= '9');
    }

    static std::pair<uint32_t, const char *> parse_hex(const char * src, int size) {
        const char * pos   = src;