Function borrow_meta 

pub exec fn borrow_meta<'a, M: AnyFrameMeta + Repr<MetaSlotStorage>>(
    ptr: ReprPtr<MetaSlotStorage, M>,
    Tracked(slot_perm): Tracked<&'a PointsTo<MetaSlot>>,
    Tracked(metadata_perm): Tracked<&'a MetadataPerm>,
    Tracked(repr_perm): Tracked<&'a M::ReprPerm>,
) -> &'a M

requires

ptr.addr() == slot_perm.addr(),

typed_meta_wf::<M>(*slot_perm, *metadata_perm, *repr_perm),

returns

typed_meta_value::<M>(*metadata_perm, *repr_perm),