It would be VERY useful if we had a slightly more flexible way of building in memory data,

Temporary tables can be OK but aren't that flexible for complex data structures and can be awkward/unpredictable when passing them around.

Json Objects/Arrays are fine but lack design time specificity and a strong type system can make code hard to follow and ease of extensibility suffers.

Dictionaries just aren't quite flexible enough for more than the simplest of requirements

A Struct (or Tuple?) like object would allow much greater freedom, for example

Struct ComplexEntity

{

     field(SourceRecord; Recordid);

     field(RelatedRecords; List of [RecordId]); 

     field(ProcessType; enum "My Process Type Enum");

}





codeunit 50000 "My Codeunit"

{

    procedure GetRecords() Result: List of [Struct ComplexEntity];

    var

        MyComplexEntiy: struct ComplexEntity;

    begin

        MyComplexEntity.SourceRecord := SomeRecordid;

        MyComplexEntity.ProcessType := enum::"My Process Type Enum"::Process1;

        MyComplexEntity.RelatedRecords.Add(SomeRelatedRecordId1);

        MyComplexEntity.RelatedRecords.Add(SomeRelatedRecordId2);

        MyComplexEntity.RelatedRecords.Add(SomeRelatedRecordId3);

        Result.Add(MyComplexEntity);

    end;



    procedure ProcessRecords()

    var

        MyEntityList: Lst of [Struct ComplexEntity];

    CurrComplexEntity: struct ComplexEntity;

        RelatedRecordId: RecordId;

        MyprocessingInterface: Interface "IProcess Interface";

    begin

        MyEntityList.AddRange(GetRecords);

        MyEntityList.AddRange(GetRecords2);

        Foreach CurrComplexEntity in MyEntityList do begin

            foreach RelatedRecordId in CurrComplexEntity.RelatedRecords do begin

                MyProcessingInterface := CurrComplexEntity.ProcessType;

                MyProcessingInterface.Process();

            end;

        end;

    end;

}

It would move us away from some of those var Record design patterns we end up having to use and allow more readable/modern code.

Extra points if we can add easy conversion to/from Json/XML ;)