std::meta::exception

 

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Defined in header <meta>
class exception : public std::exception		(since C++26)

Defines a type of object to be thrown on failure by reflection functions.

Objects of type std::meta::exception can only be created and accessed in constant evaluation.

Member functions

(constructor)	constructs a meta::exception object (public member function)
what	returns the explanatory string (public member function)
u8what	returns the explanatory string as a std::u8string_view (public member function)
from	returns the associated std::meta::info object (public member function)
where	returns the associated std::source_location (public member function)

std::meta::exception::exception

consteval exception( std::u8string_view u8what_arg, std::meta::info from, std::source_location where = std::source_location::current() ) noexcept;	(1)
consteval exception( std::string_view what_arg, std::meta::info from, std::source_location where = std::source_location::current() ) noexcept;	(2)
consteval exception( const exception& ) = default;	(3)
consteval exception( exception&& ) = default;	(4)

Constructs a new std::meta::info object. Initializes the stored values with the corresponding parameters.

1) If u8what_arg can be represented in the ordinary literal encoding, the explanatory string returned by what() is u8what_arg transcoded from UTF-8 to the ordinary literal encoding; otherwise, a call to what() is not a constant expression.

2) what_arg must be representable in UTF-8.

3) Copy constructor is defaulted.

4) Move constructor is defaulted.

std::meta::exception::what

constexpr const char* what() const noexcept override;

Returns the explanatory string passed at the time of construction, possibly transcoded from UTF-8 to the ordinary literal encoding.

std::meta::exception::u8what

consteval std::u8string_view u8what() const noexcept;

Returns the explanatory string passed at the time of construction, possibly transcoded from the ordinary literal encoding to UTF-8.

std::meta::exception::from

consteval std::meta::info from() const noexcept;

Returns the std::meta::info value passed at the time of construction.

std::meta::exception::where

consteval std::source_location where() const noexcept;

Returns the std::source_location value passed at the time of construction.