Method to_string

imperative/src/impl/transformations/grad.cpp:164–169

}

std::string GradSlot::to_string() const {
    bool has_callback = bool(callback);
    return ssprintf(
            "GradSlot{grad=%s, has_callback=%d}", m_grad.to_string().c_str(),
            (int)has_callback);
}

std::string GradFn::to_string() const {
    return ssprintf("GradFn{dests=%s}", imperative::to_string(m_dests).c_str());