Exception Handling Introduction
Exception handling in C++ manages unexpected events. It ensures a program can handle errors gracefully, without crashing. C++ uses try, catch, and throw keywords to implement this vital feature, improving software robustness and reliability.
try and catch Basics
The 'try' block encloses code that may throw an exception, while 'catch' blocks handle the exceptions. Multiple catch blocks can follow a single try, each designed to handle different exception types.
Throwing Exceptions
Using 'throw', C++ can signal the occurrence of an exception. Thrown exceptions can be primitive data types, objects, or pointers, but throwing objects is the standard practice for leveraging polymorphism.
Standard Exception Classes
C++ provides a hierarchy of exception classes in <stdexcept>. These include logic_error, runtime_error, and their subclasses, catering to different standard error types, encouraging reusable and readable exception handling.
Stack Unwinding Process
When an exception is thrown, C++ 'unwinds' the stack, destroying local objects in reverse order of creation, until it finds a matching catch. This automatic cleanup process helps prevent resource leaks.
Custom Exception Classes
Developers can define custom exception classes by inheriting from std::exception. This enables adding context-specific information and handling errors more precisely, improving debugging and maintenance.
noexcept Keyword Usage
Functions can be declared 'noexcept' to indicate they don’t throw exceptions. This can optimize performance as the compiler may make certain assumptions, but misuse can lead to program termination if an exception is thrown.
Which keywords implement C++ exception handling?
include, function, return
try, catch, throw
class, new, delete
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