I'm creating a helper package to pop payloads from a queue. It's essential that this helper be agnostic to the struct used by the application importing it.
This (no-op, just example) function will provide a single payload from the queue, of the provided type like interface{}:
func One(like interface{}) interface{} {
typ := reflect.TypeOf(like)
one := reflect.New(typ)
return one.Interface()
}
This function provides many payloads:
func Many(num int, like interface{}) interface{} {
typ := reflect.TypeOf(like)
many := reflect.MakeSlice(reflect.SliceOf(typ), num, num)
for i := 0; i < num; i++ {
one := One(typ)
many.Index(i).Set(one)
}
return many.Interface()
}
An example of usage is:
type Payload struct {
Id int
Text string
}
func main() {
Many(4, Payload{})
}
However, the above results in:
panic: reflect.Set: value of type **reflect.rtype is not assignable to type main.Payload
You're calling reflect.TypeOf on a reflect.Value, which is where **reflect.rtype is coming from.
Call your One function wth the like value directly, and assign that result to the slice.
func One(like interface{}) interface{} {
typ := reflect.TypeOf(like)
one := reflect.New(typ)
return one.Interface()
}
func Many(num int, like interface{}) interface{} {
typ := reflect.TypeOf(like)
many := reflect.MakeSlice(reflect.SliceOf(typ), num, num)
for i := 0; i < num; i++ {
one := One(like)
many.Index(i).Set(reflect.ValueOf(one).Elem())
}
return many.Interface()
}