Standard library header <contract>
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                    This header is part of the error handling library.
 Classes | |
|    (C++20)  | 
   provides information about contract violation generated by an implementation   (class)  | 
Synopsis
namespace std { class contract_violation; }
Class std::contract_violation
class contract_violation { public: uint_least32_t line_number() const noexcept; string_view file_name() const noexcept; string_view function_name() const noexcept; string_view comment() const noexcept; string_view assertion_level() const noexcept; };