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Explain the use of Go's error wrapping and error annotations for propagating and debugging errors in Go programs?

The use of Go's error wrapping and error annotations are as follows:

In Go, errors are often wrapped to add context and help with debugging. Error wrapping allows additional information to be added to an error without losing the original error message. It's a way of annotating errors with more contextual information.

The **fmt.Errorf** function can be used to wrap an error with a string message. For example:

err := someFunction()
if err != nil {
  return fmt.Errorf("failed to do something: %w", err)
}

In the example above, **fmt.Errorf** is used to wrap the error returned by **someFunction** with the message "failed to do something". The **%w** verb is used to indicate that the wrapped error should be preserved for later inspection.

Error annotations are another way of adding contextual information to errors. Error annotations use the **errors.Is** and **errors.As** functions to check if an error contains certain properties. For example:

if errors.Is(err, io.EOF) {
  fmt.Println("End of file reached")
}

var e *MyCustomError
if errors.As(err, &e) {
  fmt.Println("My custom error occurred:", e.Details)
}

In the first example, **errors.Is** is used to check if the error is an **io.EOF** error. In the second example, **errors.As** is used to check if the error is a custom error type (**MyCustomError**) and extract the error details.

Overall, error wrapping and error annotations are powerful tools for adding context and debugging information to errors in Go programs.

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