kcenon::common::error_category Class Reference

Abstract base class for error code categories. More...

#include <error_category.h>

Inheritance diagram for kcenon::common::error_category:

Collaboration diagram for kcenon::common::error_category:

Public Member Functions
virtual	~error_category ()=default
	Virtual destructor for proper cleanup of derived classes.
virtual std::string_view	name () const noexcept=0
	Returns the unique name of this error category.
virtual std::string	message (int code) const =0
	Returns a human-readable message for the given error code.
virtual bool	equivalent (int code, const error_category &other_category, int other_code) const noexcept
	Checks if an error code in this category is equivalent to another.
bool	operator== (const error_category &other) const noexcept
	Equality comparison between categories.
bool	operator!= (const error_category &other) const noexcept
	Inequality comparison between categories.
bool	operator< (const error_category &other) const noexcept
	Less-than comparison for use in ordered containers.

Protected Member Functions
	error_category ()=default
	Protected default constructor.
	error_category (const error_category &)=delete
error_category &	operator= (const error_category &)=delete
	error_category (error_category &&)=delete
error_category &	operator= (error_category &&)=delete

Detailed Description

Abstract base class for error code categories.

Each system can define its own error category by inheriting from this class. Categories provide:

• A unique name for identification
• Human-readable messages for error codes
• Equivalence comparison between different categories

Example implementation:

class network_error_category : public error_category {
public:
    static const network_error_category& instance() {
        static network_error_category instance;
        return instance;
    }
 
    std::string_view name() const noexcept override { return "network"; }
 
    std::string message(int code) const override {
        switch (code) {
            case 1: return "Connection failed";
            case 2: return "Timeout";
            default: return "Unknown network error";
        }
    }
};

Definition at line 74 of file error_category.h.

Constructor & Destructor Documentation

~error_category()

virtual kcenon::common::error_category::~error_category ( )

virtualdefault

Virtual destructor for proper cleanup of derived classes.

error_category() [1/3]

kcenon::common::error_category::error_category ( )

protecteddefault

Protected default constructor.

Categories should be accessed through their singleton instance(), not constructed directly.

error_category() [2/3]

kcenon::common::error_category::error_category ( const error_category & )

protecteddelete

error_category() [3/3]

kcenon::common::error_category::error_category ( error_category && )

protecteddelete

Member Function Documentation

equivalent()

virtual bool kcenon::common::error_category::equivalent ( int code, const error_category & other_category, int other_code ) const

inlinevirtualnoexcept

Checks if an error code in this category is equivalent to another.

The default implementation checks for exact category and code match. Derived classes can override this to provide semantic equivalence (e.g., "timeout" errors from different systems may be equivalent).

Parameters

code	Error code in this category
other_category	Category of the other error code
other_code	The other error code value

Returns

true if the error codes are semantically equivalent

Definition at line 111 of file error_category.h.

                                                         {
        return (this == &other_category) && (code == other_code);
    }

message()

virtual std::string kcenon::common::error_category::message ( int code ) const

pure virtual

Returns a human-readable message for the given error code.

Parameters

code	The error code value

Returns

Human-readable error message

Implemented in kcenon::common::common_error_category.

Referenced by kcenon::common::typed_error_code::message().

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name()

virtual std::string_view kcenon::common::error_category::name ( ) const

pure virtualnoexcept

Returns the unique name of this error category.

The name should be a short, descriptive identifier for the category. Examples: "common", "network", "database", "logger"

Returns

Category name as a string view (must be valid for lifetime of category)

Implemented in kcenon::common::common_error_category.

Referenced by kcenon::common::typed_error_code::category_name().

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operator!=()

bool kcenon::common::error_category::operator!= ( const error_category & other ) const

inlinenoexcept

Inequality comparison between categories.

Definition at line 134 of file error_category.h.

                                                                {
        return !(*this == other);
    }

operator<()

bool kcenon::common::error_category::operator< ( const error_category & other ) const

inlinenoexcept

Less-than comparison for use in ordered containers.

Definition at line 141 of file error_category.h.

                                                               {
        return std::less<const error_category*>()(this, &other);
    }

operator=() [1/2]

error_category & kcenon::common::error_category::operator= ( const error_category & )

protecteddelete

operator=() [2/2]

error_category & kcenon::common::error_category::operator= ( error_category && )

protecteddelete

operator==()

bool kcenon::common::error_category::operator== ( const error_category & other ) const

inlinenoexcept

Equality comparison between categories.

Categories are compared by identity (address), not by name. This ensures that two different categories with the same name are not considered equal.

Parameters

other

Category to compare with

Returns

true if same category instance

Definition at line 127 of file error_category.h.

                                                                {
        return this == &other;
    }

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The documentation for this class was generated from the following file:

• include/kcenon/common/error/error_category.h