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

Why Does reflect.MakeSlice Return an Un-addressable Value?

Obtaining a Slice Pointer Using Reflection

To retrieve a pointer to a slice using reflection, utilize reflect.New():

my := &My{}
myType := reflect.TypeOf(my)
slice := reflect.MakeSlice(reflect.SliceOf(myType), 10, 10)
x := reflect.New(slice.Type())
x.Elem().Set(slice)

Remember to use x.Interface() to prevent passing the reflect.Value instead of the actual value to your function.

Understanding Un-addressability in reflect.MakeSlice

An addressable value ensures that its address points to a meaningful location. Allocations made on the stack within a function do not guarantee this, hence they are not addressable.

reflect.MakeSlice assigns values to a local slice on the heap without addressing them as elements of arrays, structs, or dereferenced pointers. Therefore, it returns an un-addressable Value.

Why Require a Slice Pointer?

Often, in functions like mgo's iter.All, pointers are necessary because slices are often appended to. Appending changes the slice's memory address, which needs to be communicated to the caller.

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