Исходники и презентации

lessons/errors/errors_value_checking/main.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+)
+
+var ErrDatabaseProblem = errors.New("database problem")
+
+func GetDataFromDB() error {
+	return fmt.Errorf("failed to get data: %w", ErrDatabaseProblem)
+}
+
+func main() {
+	err := GetDataFromDB()
+	if err == ErrDatabaseProblem {
+		fmt.Println(err.Error())
+	} else if err != nil {
+		fmt.Println("unknown error")
+	}
+}