Why is this happening? Because one of my argument must be a slice address.

Maybe I did not made it clear for everyone.

collection.Find(bson.M{}).All(&result)

The above code is why I need a slice address.

the result variable here is what I need. Now usually I can do this

result := make([]SomeStruct, 10, 10)

But now the SomeStruct is dynamic and I need to create the slice by using reflect.MakeSlice, So

result := reflect.MakeSlice(reflect.SliceOf(SomeType))

And it errors on : result must be a slice address.

How to get a pointer to a slice using reflection

reflect.New()
my := &My{}

// Create a slice to begin with
myType := reflect.TypeOf(my)
slice := reflect.MakeSlice(reflect.SliceOf(myType), 10, 10)

// Create a pointer to a slice value and set it to the slice
x := reflect.New(slice.Type())
x.Elem().Set(slice)

collection.Find(bson.M{}).All(x.Interface())

x.Interface()reflect.ValuexAll()

Why does reflect.MakeSlice return an un-addressable Value?

CanAddr()true

A value is addressable if it is an element of a slice, an element of an addressable array, a field of an addressable struct, or the result of dereferencing a pointer.

reflect.MakeSlice

Why a pointer to a slice?

iter.All

This behaviour is illustrated in this example on play. In essence:

// Works. Uses available storage of the slice.
    resultv.Index(1).Set(a)

// Executes but changes are lost:   
//  reflect.Append(resultv, a)

// Does not work: reflect.Value.Set using unaddressable value
//  resultv.Set(reflect.Append(resultv, a))

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