gruzovator / cfstr

golang string based types with forced upper or lower case

Case folded string types

String based types that force string case (uppercase or lowercase). Types implement Stringer, json.Marshaler and json.Unmarshaler interfaces.

Type instances can be created:

• from string with NewUpperCase or NewLowerCase function
• from json object bytes

Example 1

Force upper case for MyStruct Label field

func ExampleUpperCase() {
	type MyStruct struct {
		Label cfstr.UpperCase
	}

	a := MyStruct{Label: cfstr.NewUpperCase("Test")}
	fmt.Printf("a.Label=%s\n", a.Label)

	jsonData, err:=json.Marshal(a)
	if err!=nil {
		panic(err)
	}
	fmt.Printf("json for a: %s\n", string(jsonData))

	var b MyStruct
	if err := json.Unmarshal([]byte(`{"Label": "Test"}`), &b); err != nil {
		panic(err)
	}
	fmt.Printf("b.Label=%s\n", b.Label)

	// Output:
	// a.Label=TEST
	// json for a: {"Label":"TEST"}
	// b.Label=TEST
}

Example 2

Force lower case and define distinct type for Residency:

func ExampleLowerCase() {
	// define destinct type based on cfstr.LowerCase
	type Residency struct {
		cfstr.LowerCase
	}
	NewResidency := func(s string) Residency {
		return Residency{cfstr.NewLowerCase(s)}
	}

	r1 := NewResidency("EN")
	fmt.Printf("r1=%s\n", r1)

	jsonData, err := json.Marshal(r1)
	if err != nil {
		panic(err)
	}
	fmt.Printf("r1 json: %s\n", string(jsonData))

	var r2 Residency
	if err := json.Unmarshal([]byte(`"RU"`), &r2); err != nil {
		panic(err)
	}
	fmt.Printf("r2=%s\n", r2)

	// Output:
	// r1=en
	// r1 json: "en"
	// r2=ru
}