std::error_code:: operator bool

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Utilities library
General utilities
Relational operators (deprecated in C++20)
explicit operator bool ( ) const noexcept ;
(since C++11)

Checks if the error code value is valid, i.e. non-zero.

Parameters

(none)

Return value

false if value ( ) == 0 , true otherwise.

Notes

Although this operator is often used as a convenient shorthand to check if any error was returned, as in if ( ec ) { /* handle error */ } , such use is not robust: some error codes, for example, HTTP status code 200 , may indicate success as well.