Why error handling is required in Go - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if an error occurred after opening a file.

Go

file, err := os.Open("test.txt")
if [1] != nil {
    fmt.Println("Error opening file")
}

Drag options to blanks, or click blank then click option'

Afile

Berr

Cnil

Dos

Attempts:

3 left

💡 Hint

Common Mistakes

Checking the wrong variable for error

Not checking for nil before using the file

In Go, errors are returned as the second value. We check if err is not nil to detect an error.

2fill in blank

medium

Complete the code to handle an error returned by a function.

Go

result, [1] := divide(10, 0)
if err != nil {
    fmt.Println("Cannot divide by zero")
}

Drag options to blanks, or click blank then click option'

Afail

Berror

Ce

Derr

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name other than 'err' for errors

Ignoring the error variable

The error variable is commonly named err in Go to follow conventions and clarity.

3fill in blank

hard

Fix the error in the code that ignores error handling.

Go

file, _ := os.Open("data.txt")
[1] := file.Stat()
fmt.Println(info.Size())

Drag options to blanks, or click blank then click option'

Ainfo, err

BfileInfo

Cinfo

DfileInfo, err

Attempts:

3 left

💡 Hint

Common Mistakes

Ignoring the error returned by Stat

Using undefined variable 'info' without assignment

To handle errors properly, assign both the returned info and error from file.Stat(). This allows checking the error before using info.

4fill in blank

hard

Fill both blanks to correctly handle an error when reading a file.

Go

data, [1] := os.ReadFile("config.json")
if [2] != nil {
    fmt.Println("Failed to read file")
}

Drag options to blanks, or click blank then click option'

Aerr

Berror

Cfail

De

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names for error capture and check

Not checking the error at all

Use the variable err to capture and check the error returned by os.ReadFile.

5fill in blank

hard

Fill all three blanks to handle an error and print the file size.

Go

file, [1] := os.Open("log.txt")
if [2] != nil {
    fmt.Println("Error opening file")
    return
}
info, [3] := file.Stat()

Drag options to blanks, or click blank then click option'

Aerr

Berror

Cerr2

Dfail

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names for errors

Not checking errors before using file info

Use err consistently to capture and check errors from both os.Open and file.Stat().