package opt_test import ( "fmt" "go.jolheiser.com/opt" ) func ExampleApply() { f := &Foo{ Bar: "default", } opt.Apply(f, WithBar("override")) fmt.Println(f.Bar) // Output: // override } func ExampleApplyError() { f := &Foo{ Bar: "default", } err := opt.ApplyError(f, WithBarErr("uh oh!")) // WithBarErr always returns errors.New(b) if err != nil { fmt.Println(err) } // Output: // uh oh! }