Error Handling
Write robust code with proper error handling techniques. Learn try/catch blocks, throwing errors, custom error types, and defensive programming. Build reliable applications that gracefully handle unexpected situations.
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What You'll Learn
Try, catch, and finally blocks
Throwing errors and error types
Custom error classes
Error propagation and bubbling
Defensive programming techniques
Logging and debugging errors
Frequently Asked Questions
When should I throw an error vs return an error value?
Throw errors for exceptional conditions that shouldn't normally occur (like invalid input or system failures). Return error values for expected conditions that are part of normal control flow. Exceptions are for exceptional cases.
What is the finally block used for?
The finally block executes regardless of whether an error occurred or not. Use it for cleanup operations like closing files, releasing resources, or resetting state that must happen in both success and error cases.
Should I catch all errors or let them propagate?
Only catch errors you can meaningfully handle. Let others propagate to higher levels where they can be handled appropriately. Catching all errors without proper handling can hide bugs and make debugging harder.
Ready to Master Error Handling?
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