Add Fold testable example

fold_example_test.go

@@ -0,0 +1,25 @@
+package mo
+
+import (
+	"errors"
+	"fmt"
+)
+
+func ExampleFold() {
+	res1 := Result[int]{value: 42, isErr: false, err: nil}
+	res2 := Result[int]{value: 0, isErr: true, err: errors.New("error")}
+
+	successFunc := func(val int) string {
+		return fmt.Sprintf("Success with value %d", val)
+	}
+
+	failureFunc := func(err error) string {
+		return fmt.Sprintf("Failure with error %s", err)
+	}
+
+	fmt.Println(Fold[error, int, string](res1, successFunc, failureFunc))
+	fmt.Println(Fold[error, int, string](res2, successFunc, failureFunc))
+	// Output:
+	// Success with value 42
+	// Failure with error error
+}

result_example_test.go

@@ -346,13 +346,3 @@ func ExampleResult_FlatMap_err() {
 	fmt.Println(result.IsError(), result.OrEmpty(), result.Error())
 	// Output: true 0 error
 }
-
-func exampleResult_Fold() {
-	res := Result[int]{value: 42, err: nil}
-	foldResult := Fold[error, int, string](res, func(v int) string {
-		return "Success"
-	}, func(_ error) string {
-		return "Failure"
-	})
-	println(foldResult)
-}