Proper handling of errors and exceptional situations is essential for the continued correct operation of software (see ERR00-CPP. Adopt and implement a consistent and comprehensive error-handling policy). The preferred mechanism for reporting errors in a C++ program is exceptions (see ERR07-CPP. Use exception handling rather than using error codes). A number of core language facilities, including dynamic_cast, operator new(), and typeid, report failures by throwing exceptions. In addition, the C++ standard library makes heavy use of exceptions to report several different kinds of failures. Few C++ programs manage to avoid using some of these facilities. Consequently, the vast majority of C++ programs must be prepared for exceptions to occur and must handle each appropriately (see ERR51-CPP. Handle all exceptions).
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