where constraint with a ValueList from an entity?

I have probably missed something simple, but I can't see how I can make a `where` constraint with a `ValueList` from an entity, like this:

E.where_ (E.val SomeValue `E.notIn` (someEntity E.^. SomeArray))

I would like to match `SomeValue` against a an array (`character varying[]`).

The compilation error looks like this (where `SomeValue` is of the type `ArrayValueType`):

Expected type: E.SqlExpr (E.ValueList ArrayValueType)
Actual type: E.SqlExpr (E.Value [ArrayValueType])

Any hints would be appreciated. :)

Start with the `where_` expression and the reported `ValueList` versus `Value [ArrayValueType]` mismatch. Determine whether an entity array can be used in this constraint, then document or test the supported approach so the expression compiles.

Written by the indexing model from the issue text.