Function is_identifier_start

external/zep/src/syntax_python.cpp:22–24

    namespace {

        bool is_identifier_start(uint8_t ch) {
            return std::isalpha(static_cast<unsigned char>(ch)) != 0 || ch == '_';
        }

        bool is_identifier_continue(uint8_t ch) {
            return std::isalnum(static_cast<unsigned char>(ch)) != 0 || ch == '_';