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std::exception::exception

From cppreference.com
< cpp‎ | error‎ | exception
 
 
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(1)
exception() throw();
(until C++11)
exception() noexcept;
(since C++11)
(2)
exception( const exception& other ) throw();
(until C++11)
exception( const exception& other ) noexcept;
(since C++11)

Constructs new exception object.

1) Default constructor. what() returns an implementation-defined string.
2) Copy constructor. Initializes the contents with those of other. If *this and other both have dynamic type std::exception then std::strcmp(what(), other.what()) == 0.

[edit] Parameters

other - another exception to assign the contents of

[edit] Notes

Because copying std::exception is not permitted to throw exceptions, when derived classes (such as std::runtime_error) have to manage a user-defined diagnostic message, it is typically implemented as a copy-on-write string.

The Microsoft implementation includes non-standard constructors taking strings thus allowing instances to be thrown directly with a meaningful error message. The nearest standard equivalents are std::runtime_error or std::logic_error.

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 471 C++98 there is no requirement on what() of the exception copy added