Support for encoding parametrized lists

[edlman]

With added support for encoding parametrized lists. E.g.

  List<int> ids = [ ... ]; // init list with values or get it from parameters
  result1 = db.query("select * from table where id in (@ids)", { "ids": ids });
  result2 = db.query("select * from table where id = any (array[@ids]::int[])", { "ids": ids });

When using array[@x] syntax in query it's wise to use array type cast (::int[], ::date[], ...) to avoid problems with null list.

Signed-off-by: Martin Edlman ac@an.y-co.de

[tomyeh]

Sorry, but I think a list can have different meaning. For example, a JSON value. Also, in your example, it will cause a syntax error if the list is empty.

Maybe you can consider to introduce a class for it.

class ListValues {
   String encode();
}

class StringValues implements ListValues {
   StringValues(Iterable<String> this.values, [String this.emptyValue="''"]);
   String encode() => values.isEmpty ? emptyValue: ...;
}