go / beginner
Snippet
Error Handling: The Go Way
Go handles errors explicitly by returning error values from functions. This pattern forces developers to handle errors at each call site. The error interface has a single method Error() string. errors.New creates a simple error, while fmt.Errorf with %w wraps errors to preserve the original error chain. The nil value represents no error. Always check for errors before using the returned values.
snippet.go
go
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package mainimport ("errors""fmt")func divide(a, b int) (int, error) {if b == 0 {return 0, errors.New("division by zero")}return a / b, nil}func divideWithMessage(a, b int) (int, error) {if b == 0 {return 0, fmt.Errorf("cannot divide %d by zero: %w", a, errors.New("invalid divisor"))}return a / b, nil}func main() {result, err := divide(10, 2)if err != nil {fmt.Println("Error:", err)return}fmt.Println("Result:", result)// Handling wrapped error_, err = divideWithMessage(5, 0)if err != nil {fmt.Println("Wrapped error:", err)}}
Breakdown
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func divide(a, b int) (int, error)
Returns int result and error - Go's error handling convention
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if b == 0 { return 0, errors.New(...) }
Return zero value and error when invalid input occurs
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return a / b, nil
Return result and nil error on success
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fmt.Errorf("...%w...", err)
%w verb creates wrapped error preserving error chain for errors.Is/As