Exception Handling in C++: The exception handling in C++ is the process to handle runtime errors. A C++ exception is a response to an exceptional circumstance that arises while a program is running, such as an attempt to divide by zero. Exceptions provide a way to transfer control from one part of a program to another. All exceptions are derived from std:: exception class. It is a runtime error that can be handled. If we don’t handle the exception, it prints the exception message and terminates the program.
Exception Handling in C++
In C++ exception handling can be done by using the three keywords. They are as follows:
- try: represents a block of code that can throw an exception.
- catch: represents a block of code that is executed when a particular exception is thrown.
- throw: Used to throw an exception. Also used to list the exceptions that a function throws, but doesn’t handle itself.
C++ Common Exceptions
| Exception | Description |
|---|---|
| std::exception | an exception and parent class of all standard C++ exceptions |
| std::logic_failure | an exception that can be detected by reading a code |
| std::runtime_error | the exception that cannot be detected by reading a code |
| std::bad_exception | used to handle the unexpected exceptions in a c++ program |
| std::bad_cast | the exception is generally be thrown by dynamic_cast |
| std::bad_typeid | an exception is generally be thrown by typeid |
| std::bad_alloc | the exception is generally be thrown by new |
Exceptions derived directly from the exception class
| Exception | Description |
|---|---|
| bad_alloc | occurs when there is a failure of memory allocation |
| bad_cast | Is thrown when dynamic_cast is used incorrectly |
| bad_exception | is thrown by the unexpected handler |
| bad_function_call | Thrown when an empty (not implemented) function is called |
| bad_typeid | Thrown by typeid function |
| bad_weak_ptr | An exception that can be thrown by the shared_ptr class constructor |
| ios_base::failure | Base class for all the stream exceptions |
| logic_error | Base class for some logic error exceptions |
| runtime_error | Base class for some runtime error exceptions |
Exception derived directly from exception class through logic_error
| Exception | Description |
|---|---|
| domain_error | Thrown when an error of function domain happens |
| future_error | Reports an exception that can happen in future objects(See more info about future class) |
| invalid_argument | An exception is thrown when an invalid argument is passed |
| length_error | Is thrown when the incorrect length is set |
| out_of range error | thrown when out of range index is used |
Exceptions that are derived indirectly from exception class through runtime_error
| Exception | Description |
|---|---|
| overflow_error | Arithmetic overflow exception |
| range_error | Signals range error in computations |
| system_error | Reports an exception from the operating system |
| underflow_error | Arithmetic underflow exceptions |