Implementation:Rapidsai Cuml FIL Exceptions

Knowledge Sources	Rapidsai_Cuml
Domains	Machine_Learning, Forest_Inference
Last Updated	2026-02-08 12:00 GMT

Overview

Defines custom exception types for the Forest Inference Library (FIL) to signal model compatibility, import, and data type errors.

Description

This header provides three exception classes within the ML::fil namespace, all derived from std::exception:

• unusable_model_exception: Thrown when a model is incompatible with FIL. Supports construction with no arguments (default message: "Model is not compatible with FIL"), a std::string, or a const char*. Stores the message in a std::string member.

• model_import_error: Thrown when model import fails. Supports construction with no arguments (default message: "Error while importing model") or a const char*. Stores the message as a raw const char*.

• type_error: Thrown when there is a mismatch between the input data type and the model's expected type (e.g., providing doubles to a float-threshold model). Supports construction with no arguments (default message: "Model cannot be used with given data type") or a const char*. Stores the message as a raw const char*.

All three exceptions provide a what() method returning a human-readable error description.

Usage

Use these exceptions when working with FIL model loading and inference code. Catch unusable_model_exception to handle cases where a model format is unsupported, model_import_error for import failures, and type_error for precision mismatches between model and input data.

Code Reference

Source Location

• Repository: Rapidsai_Cuml
• File: cpp/include/cuml/fil/exceptions.hpp

Signature

namespace ML {
namespace fil {

struct unusable_model_exception : std::exception {
  unusable_model_exception();
  unusable_model_exception(std::string msg);
  unusable_model_exception(char const* msg);
  virtual char const* what() const noexcept;
 private:
  std::string msg_;
};

struct model_import_error : std::exception {
  model_import_error();
  model_import_error(char const* msg);
  virtual char const* what() const noexcept;
 private:
  char const* msg_;
};

struct type_error : std::exception {
  type_error();
  type_error(char const* msg);
  virtual char const* what() const noexcept;
 private:
  char const* msg_;
};

}  // namespace fil
}  // namespace ML

Import

#include <cuml/fil/exceptions.hpp>

I/O Contract

Inputs

Name	Type	Required	Description
msg	std::string or char const*	No	Custom error message (defaults provided for all exception types)

Outputs

Name	Type	Description
what()	char const*	Human-readable error description string

Usage Examples

#include <cuml/fil/exceptions.hpp>
#include <iostream>

void load_and_validate_model(/* model parameters */) {
    try {
        // Attempt to import a tree model into FIL
        // ... model loading code ...

        // Check model compatibility
        bool model_supported = /* check model format */;
        if (!model_supported) {
            throw ML::fil::unusable_model_exception(
                "Model uses unsupported split type for FIL");
        }

        // Check data type compatibility
        bool types_match = /* check float vs double */;
        if (!types_match) {
            throw ML::fil::type_error(
                "Input data is double but model expects float thresholds");
        }

    } catch (const ML::fil::unusable_model_exception& e) {
        std::cerr << "Model not usable: " << e.what() << std::endl;
    } catch (const ML::fil::model_import_error& e) {
        std::cerr << "Import failed: " << e.what() << std::endl;
    } catch (const ML::fil::type_error& e) {
        std::cerr << "Type mismatch: " << e.what() << std::endl;
    }
}

Related Pages

• Environment:Rapidsai_Cuml_CUDA_GPU