Major Description
When using the DSL for updates, the set/unset take an Expression as the update-for-clause. This clause, in the form of FOR variable IN path WHEN condition END, is not trivial but not complex enough that it warrants reworking of the global DSL.
A helper class could be introduced to guide users in producing the adequate Expression. Usage would be like:
UpdateForClause.forIn("variable", "path").when(x("condition")) |