diff --git a/objc/objc_runtime_darwin.go b/objc/objc_runtime_darwin.go
index 73e1e881..a35fe5b3 100644
--- a/objc/objc_runtime_darwin.go
+++ b/objc/objc_runtime_darwin.go
@@ -554,7 +554,7 @@ type IMP uintptr
 func NewIMP(fn interface{}) IMP {
 	ty := reflect.TypeOf(fn)
 	if ty.Kind() != reflect.Func {
-		panic("objc: not a function")
+		panic(fmt.Sprintf("objc: not a function"))
 	}
 	// IMP is stricter than a normal callback
 	// id (*IMP)(id, SEL, ...)
diff --git a/objc/objc_runtime_darwin_test.go b/objc/objc_runtime_darwin_test.go
index 08e51198..9aa35d2d 100644
--- a/objc/objc_runtime_darwin_test.go
+++ b/objc/objc_runtime_darwin_test.go
@@ -12,6 +12,30 @@ import (
 	"github.com/ebitengine/purego/objc"
 )
 
+func ExampleRegisterClass_helloworld() {
+	class, err := objc.RegisterClass(
+		"FooObject",
+		objc.GetClass("NSObject"),
+		nil,
+		nil,
+		[]objc.MethodDef{
+			{
+				Cmd: objc.RegisterName("run"),
+				Fn: func(self objc.ID, _cmd objc.SEL) {
+					fmt.Println("Hello World!")
+				},
+			},
+		},
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	object := objc.ID(class).Send(objc.RegisterName("new"))
+	object.Send(objc.RegisterName("run"))
+	// Output: Hello World!
+}
+
 func ExampleRegisterClass() {
 	var (
 		sel_new    = objc.RegisterName("new")
@@ -66,10 +90,52 @@ func ExampleIMP() {
 	})
 
 	purego.SyscallN(uintptr(imp), 105, 567, 9, 2, 3, ^uintptr(4), 4, 8, 9)
-
 	// Output: IMP: 105 567 9 2 3 -5 4 8 9
 }
 
+func ExampleID_SendSuper() {
+	super, err := objc.RegisterClass(
+		"SuperObject",
+		objc.GetClass("NSObject"),
+		nil,
+		nil,
+		[]objc.MethodDef{
+			{
+				Cmd: objc.RegisterName("doSomething"),
+				Fn: func(self objc.ID, _cmd objc.SEL) {
+					fmt.Println("In Super!")
+				},
+			},
+		},
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	child, err := objc.RegisterClass(
+		"ChildObject",
+		super,
+		nil,
+		nil,
+		[]objc.MethodDef{
+			{
+				Cmd: objc.RegisterName("doSomething"),
+				Fn: func(self objc.ID, _cmd objc.SEL) {
+					fmt.Println("In Child")
+					self.SendSuper(_cmd)
+				},
+			},
+		},
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	objc.ID(child).Send(objc.RegisterName("new")).Send(objc.RegisterName("doSomething"))
+	// Output: In Child
+	// In Super!
+}
+
 func TestSend(t *testing.T) {
 	// NSNumber comes from Foundation so make sure we have linked to that framework.
 	_, err := purego.Dlopen("/System/Library/Frameworks/Foundation.framework/Foundation", purego.RTLD_GLOBAL)
@@ -97,8 +163,48 @@ func ExampleSend() {
 	subString := objc.ID(class_NSString).Send(sel_stringWithUTF8String, "lo, Wor\x00")
 
 	r := objc.Send[NSRange](fullString, objc.RegisterName("rangeOfString:"), subString)
-
 	fmt.Println(r)
-
 	// Output: {3 7}
 }
+
+func ExampleSendSuper() {
+	super, err := objc.RegisterClass(
+		"SuperObject2",
+		objc.GetClass("NSObject"),
+		nil,
+		nil,
+		[]objc.MethodDef{
+			{
+				Cmd: objc.RegisterName("doSomething"),
+				Fn: func(self objc.ID, _cmd objc.SEL) int {
+					return 16
+				},
+			},
+		},
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	child, err := objc.RegisterClass(
+		"ChildObject2",
+		super,
+		nil,
+		nil,
+		[]objc.MethodDef{
+			{
+				Cmd: objc.RegisterName("doSomething"),
+				Fn: func(self objc.ID, _cmd objc.SEL) int {
+					return 24
+				},
+			},
+		},
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	res := objc.SendSuper[int](objc.ID(child).Send(objc.RegisterName("new")), objc.RegisterName("doSomething"))
+	fmt.Println(res)
+	// Output: 16
+}