Perl - best practices in dealing with invalid data passed to a sub

Dealing with Invalid Data Passed to a Subroutine

When working with subroutine calls, it's crucial to have a strategy for handling invalid data. Several methods are available in Perl:

• Return Codes: Use specific error codes to indicate data issues.
• Return undef: Indicate a failed operation by returning undef.
• Throw Exceptions: Utilize the die function to throw exceptions and provide detailed error messages.

The best approach depends on the context and the behavior of the code.

Considerations

Returning undef can be a simple approach, but it may conflict with legitimate return values, leading to confusion.

Throwing exceptions using die allows for more informative error messages. For complex code, consider creating an error-handling class to provide structured error reporting.

Example

When dealing with invalid input, it's often advisable to throw a die with a specific error message. This helps isolate the error and facilitates debugging.

my $input = get_input();
die "Invalid input" if !defined $input;

Best Practices

There is no absolute "best practice" for handling invalid data.

However, it's generally recommended to use die when an error cannot be recovered from and to provide clear error messages. For complex code, error-handling classes can improve error reporting and recovery.

Experimental Features

Perl 5.34.0 introduced an experimental try/catch control structure. It allows for exception handling similar to the try/catch pattern in other languages.