Go Error Handling

What is Error Handling?

In Go, errors are handled explicitly using return values instead of exceptions.

Functions often return two values: the result and an error.

Returning Errors from Functions

Functions can return an error using the built-in error type.

If no error occurs, return nil.

Checking Errors

Always check if an error is not nil before using the result.

This prevents runtime issues and ensures safe execution.

Ignoring Errors (Not Recommended)

You can ignore errors using the blank identifier _, but this is discouraged.

Ignoring errors can lead to bugs and unexpected behavior.

Creating Custom Errors

You can create custom error messages using fmt.Errorf or errors.New.

This helps provide meaningful feedback when something goes wrong.

Using panic

The panic function stops normal execution of the program.

It should only be used for serious, unexpected errors.

Using recover

The recover function can catch a panic and prevent the program from crashing.

It must be used inside a deferred function.

Real-World Example

Error handling is used in almost every Go program, especially when working with files or APIs.

Why Error Handling is Important

Go encourages explicit error handling to make programs more predictable and reliable.

• Prevents crashes
• Makes bugs easier to trace
• Improves code clarity

Common Mistakes

Be careful with these:

• Ignoring errors
• Not checking err != nil
• Using panic unnecessarily

Practice

Create a function that divides two numbers and returns an error if dividing by zero.

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