No collections are supported, just not at the root.

Imported arrays and collections must have at least 1 item prefilled and items must be homogenous in order for the import to work.

+++ Rick ---

>>The root object cannot be a collection...
>>
>>+++ Rick ---
>
>I guess that it means that no object contained at any level of the root object can be a collection (as in my example the root class does not inherit of Collection). I can imagine the problems that heterogeneous collections can cause. Unfortunately, as far as I can see, most objects that I will be willing to persist contain a (homogeneous) collection in some place.
>I saw the remark about arrays in the documentation, saying that an array could be imported only if it was homogeneous and in the template object one has populated the first element with a value of the right type. Does it mean that it would work if I replaced the VFP collection class by a custom collection class of mine based on an array ? That is, given that in the template object I will always populate any collection with at least one element of the right type.
>
>David