Free GoLang Error Handling Questions and Answers

Question 1

Which package is used to create and handle errors in Go?

Accepted Answer

errors

Answer

The `errors` package in Go provides fundamental interfaces and functions for error handling. Specifically, `errors.New` is used to create a simple error message. While `fmt` can format error messages and `log` can output them, `errors` is the dedicated package for defining and working with error types.

Question 2

What is the idiomatic way to handle errors in Go?

Accepted Answer

Check if the returned error is nil.

Answer

Go's idiomatic error handling involves functions returning an `error` as their last return value. Callers then check if this returned error is `nil`; a `nil` error indicates success, while a non-`nil` error indicates that something went wrong. This explicit check promotes robust error handling without relying on exceptions or try-catch blocks.

Question 3

Which of the following methods can be used to create a custom error in Go?

Accepted Answer

errors.New("custom error")

Answer

In Go, you can create custom errors in several ways. `errors.New("custom error")` creates a simple error with a static message. `fmt.Errorf("custom error: %v", value)` creates a formatted error, often including dynamic information. Implementing the `Error() string` method for a custom struct type allows for more complex, typed errors.

Question 4

When should panic be used instead of returning an error in Go?

Accepted Answer

When an unexpected and unrecoverable condition occurs.

Answer

`panic` in Go should be reserved for truly exceptional and unrecoverable situations, such as programming errors or critical system failures that prevent the program from continuing safely. For most anticipated errors, returning an `error` value is the idiomatic and preferred approach, allowing the caller to handle or recover gracefully. Using `panic` for minor errors would lead to program crashes.

GO - Golang Online Test Practice Test

GO - Golang Online Test Practice Test

Free GoLang Error Handling Questions and Answers