Question

Give several reasons why exception-handling techniques should not be used for conventional program control.

Short answer

Exceptions should be reserved for error handling, not conventional control, to maintain code readability, performance, and ease of debugging.

Step-by-step solution

Understand Exception Handling

Exception handling is a set of constructs in some programming languages used to manage exceptions—unexpected events or errors that occur during program execution.

Define Conventional Program Control

Conventional program control refers to the normal or expected flow of execution in a program, which is structured using constructs like loops, conditionals, and function calls.

Exception Use in Error Handling

Exceptions are primarily designed for error handling and recovery from unexpected conditions, whereas conventional program control is designed for handling the standard, expected flow of execution.

Impact on Program Readability

Using exceptions for program control can make the program code less readable. It obscures the intended program logic by mixing error handling with normal control flow, making it difficult to follow the sequence of execution.

Performance Overhead

Exception handling mechanisms often introduce a performance overhead. Using exceptions for program control instead of error handling can make the program unnecessarily slow, as exception handling is more resource-intensive than standard control mechanisms.

Complexity in Debugging

Using exceptions for normal program control can introduce complexity in debugging. Whereas normal control structures have clear pathways, exceptions create non-linear execution paths, making it harder to trace the flow of execution during debugging.

Conclusion

For conventional program control flow, using standard constructs ensures clarity and performance, while exceptions should be reserved for handling and managing unexpected error conditions.

Key concepts

Program Readability

When writing code, especially in a collaborative environment, it's crucial for the code to be easily understandable. This is where program readability comes into play. Using exception handling techniques for regular program control can obscure the main logic of the program. Exception handling can intertwine error management with the primary flow of the application, making it difficult to discern the intended functionality from error handling routines.

A well-structured program with clear flow control constructs like loops and conditionals allows other developers to easily read, understand, and maintain the code. Adding exceptions into this mix without proper reason can significantly reduce readability, leading to confusion and potentially more errors down the line.

Performance Overhead

Performance overhead refers to the resource costs associated with executing a particular piece of code. Exception handling in C++ is designed to handle errors and manage unexpected situations. However, this process is not free in terms of computing resources.

Using exceptions for normal flow control, instead of dedicated error scenarios, can impose unnecessary overhead on the system. This can make your program slower because executing try-catch blocks is more resource-intensive than regular control structures like loops and conditionals.

To optimize your code's performance, avoid using exceptions as a substitute for regular logic control. Keep them reserved for unexpected errors and conditions to minimize the stress on system capabilities.

Debugging Complexity

Debugging is an important step in the software development lifecycle. It involves identifying, isolating, and fixing errors in the codebase. Exception handling, when used outside its intended purpose, can add a layer of complexity to this process.

Standard programming constructs offer a linear and predictable path of execution. However, exceptions can cause jumps in the code execution, creating non-linear paths that are much harder to follow and debug.

• Standard control flows are predictable and straightforward to trace.
• Exception-driven paths can appear sporadic and interrupt the natural flow.

By sticking to conventional control methods for typical operations and reserving exceptions for actual error handling, developers can keep debugging processes easier and more efficient.

Error Handling

One of the primary purposes of exceptions in C++ is error handling. Exception mechanisms are designed to catch and properly deal with unforeseen errors during program execution. They provide a robust means to transfer control to error handling code when things don't go as planned.

Exceptions should ideally be used to capture critical errors which cannot be managed by normal program logic. This allows you to isolate error handling codes from the main code, promoting modularity and separation of concerns.

Using exceptions appropriately helps ensure that errors are dealt with in a consistent and controlled manner, ultimately improving the reliability and maintainability of your code. Therefore, save exception handling for situations where errors might otherwise cause the program to fail or behave unexpectedly, rather than for standard program control.