func TestCall(t *testing.T) {
if ret, err := function.Call(get, 1, 2); err != nil {
t.Fail()
} else {
if ret[0].(int) != 3 || ret[1] != nil {
t.Fail()
}
}
}
// Call the method 'method' of 't', and return (ReturnedValue, nil) if calling
// successfully, which ReturnedValue is the result which that method returned.
// Or return (nil, Error).
func CallMethod(t interface{}, method string, args ...interface{}) ([]interface{}, error) {
if m := GetMethod(t, method); m == nil {
return nil, NotHaveMethod
} else {
_args := make([]interface{}, len(args)+1)
_args[0] = t
copy(_args[1:], args)
return function.Call(m, _args...)
}
}
func TestCallWithPointer(t *testing.T) {
f := func(v *int) (old int) {
old = *v
*v += 1
return
}
v := 1
ret, _ := function.Call(f, &v)
// The returned value is the old, which is 1, and v became 2.
if ret[0].(int) != 1 || v != 2 {
t.Fail()
}
}
func ExampleCall() {
f := func(i int, j int) (int, error) {
return i + j, errors.New("This is not an error")
}
ret, _ := function.Call(f, 1, 2)
// Since the first result is an integer, and it's not necessary to check
// whether it is nil, so you may omit it, and infer this type directly.
if ret[0] != nil {
fmt.Println(ret[0].(int))
}
// Since the second result may be nil, so you MUST check whether it is nil firstly.
if ret[1] != nil {
fmt.Println(ret[1].(error))
}
// Output:
// 3
// This is not an error
}