feat: add UnwarpOr and UnwarpOrDefault to pointer pkg (#116)

pointer/pointer.go

@@ -18,6 +18,26 @@ func Unwrap[T any](p *T) T {
 	return *p
 }
 
+// UnwarpOr returns the value from the pointer or fallback if the pointer is nil.
+// Play: https://go.dev/play/p/mmNaLC38W8C
+func UnwarpOr[T any](p *T, fallback T) T {
+	if p == nil {
+		return fallback
+	}
+	return *p
+}
+
+// UnwarpOrDefault returns the value from the pointer or the default value if the pointer is nil.
+// Play: https://go.dev/play/p/ZnGIHf8_o4E
+func UnwarpOrDefault[T any](p *T) T {
+	var v T
+
+	if p == nil {
+		return v
+	}
+	return *p
+}
+
 // ExtractPointer returns the underlying value by the given interface type
 // Play: https://go.dev/play/p/D7HFjeWU2ZP
 func ExtractPointer(value any) any {

pointer/pointer_examples_test.go

@@ -29,6 +29,54 @@ func ExampleUnwrap() {
 	// abc
 }
 
+func ExampleUnwarpOr() {
+	a := 123
+	b := "abc"
+
+	var c *int
+	var d *string
+
+	result1 := UnwarpOr(&a, 456)
+	result2 := UnwarpOr(&b, "abc")
+	result3 := UnwarpOr(c, 456)
+	result4 := UnwarpOr(d, "def")
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+	fmt.Println(result4)
+
+	// Output:
+	// 123
+	// abc
+	// 456
+	// def
+}
+
+func ExampleUnwarpOrDefault() {
+	a := 123
+	b := "abc"
+
+	var c *int
+	var d *string
+
+	result1 := UnwarpOrDefault(&a)
+	result2 := UnwarpOrDefault(&b)
+	result3 := UnwarpOrDefault(c)
+	result4 := UnwarpOrDefault(d)
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+	fmt.Println(result4)
+
+	// Output:
+	// 123
+	// abc
+	// 0
+	//
+}
+
 func ExampleExtractPointer() {
 	a := 1
 	b := &a

pointer/pointer_test.go

@@ -30,6 +30,40 @@ func TestUnwrap(t *testing.T) {
 	assert.Equal(b, Unwrap(&b))
 }
 
+func TestUnwarpOr(t *testing.T) {
+	t.Parallel()
+
+	assert := internal.NewAssert(t, "TestUnwarpOr")
+
+	a := 123
+	b := "abc"
+
+	var c *int
+	var d *string
+
+	assert.Equal(a, UnwarpOr(&a, 456))
+	assert.Equal(b, UnwarpOr(&b, "abc"))
+	assert.Equal(456, UnwarpOr(c, 456))
+	assert.Equal("def", UnwarpOr(d, "def"))
+}
+
+func TestUnwarpOrDefault(t *testing.T) {
+	t.Parallel()
+
+	assert := internal.NewAssert(t, "TestUnwarpOrDefault")
+
+	a := 123
+	b := "abc"
+
+	var c *int
+	var d *string
+
+	assert.Equal(a, UnwarpOrDefault(&a))
+	assert.Equal(b, UnwarpOrDefault(&b))
+	assert.Equal(0, UnwarpOrDefault(c))
+	assert.Equal("", UnwarpOrDefault(d))
+}
+
 func TestExtractPointer(t *testing.T) {
 	t.Parallel()