Error Handling

Error Handling is important because not everything goes as expected in our programs. We need to handle error so we can decide what to do when an error shows up.

A lot of things could go wrong like:

• Network problems.
• File access problems.
• User input problems etc.

Nil value means that the value is not initialized yet. It is extensively used for Error Handling and means there is no error.

It is also a zero value for pointer-based types like Pointers, Slices, Maps, Interfaces and Channels.

Error Handling Example

func main() {
    age := os.Args[1]

	n, err := strconv.Atoi(age)

	if err != nil { // checks whether there is an error or not
		fmt.Println("ERROR:", err)
		return
	}

	fmt.Printf("SUCCESS: Converted %q to %d.\n", age, n)
}

When we call a function that returns an error, we should always check for the error immediately after the call to that function. This is to prevent unnecessary bugs when running our programs.

Usage

go run main.go 50