Function lightgbm_sys::LGBM_BoosterDumpModel

pub unsafe extern "C" fn LGBM_BoosterDumpModel(
    handle: BoosterHandle, 
    start_iteration: c_int, 
    num_iteration: c_int, 
    feature_importance_type: c_int, 
    buffer_len: i64, 
    out_len: *mut i64, 
    out_str: *mut c_char
) -> c_int

\brief Dump model to JSON. \param handle Handle of booster \param start_iteration Start index of the iteration that should be dumped \param num_iteration Index of the iteration that should be dumped, <= 0 means dump all \param feature_importance_type Type of feature importance, can be C_API_FEATURE_IMPORTANCE_SPLIT or C_API_FEATURE_IMPORTANCE_GAIN \param buffer_len String buffer length, if buffer_len < out_len, you should re-allocate buffer \param[out] out_len Actual output length \param[out] out_str JSON format string of model, should pre-allocate memory \return 0 when succeed, -1 when failure happens