Lesson 12 of 15

Error Handling in Go

Handle errors clearly and safely using Go's error values.

Beginner Friendly Runnable Example Go Programming

Learning objective: Return and check error values in a simple function.

Go Error Style

Go handles errors using returned error values rather than exceptions. This makes error handling explicit.

Checking Errors

Always check whether an error has occurred before using a result that may not be valid.

Creating Errors

You can create your own error messages using the errors package.

Example Code

Create or update your Go file, then run the program using go run main.go.

package main

import (
    "errors"
    "fmt"
)

func divide(a float64, b float64) (float64, error) {
    if b == 0 {
        return 0, errors.New("cannot divide by zero")
    }
    return a / b, nil
}

func main() {
    result, err := divide(10, 0)

    if err != nil {
        fmt.Println("Error:", err)
        return
    }

    fmt.Println("Result:", result)
}

Key points to remember

A nil error means no error occurred.
Check errors immediately after calling a function that can fail.
Clear error messages help users and developers understand the problem.

Practice Exercises

Create a divide function.
Return an error when input is invalid.
Check and print error messages.

Continue Learning

After this lesson, continue to the next lesson or explore related tutorials on VisualStudioTutor.com.