I have a theory that I could use an HL7 Data Transformer in a rule without specifying a specific DocType. I want to use the same DTL for a variety of different DocTypes. Here is my very simplistic DTL so far:

Class OrdRes.TestTransform Extends Ens.DataTransformDTL [ DependsOn = EnsLib.HL7.Message ]
{
    Parameter IGNOREMISSINGSOURCE = 1;
    Parameter REPORTERRORS = 1;
    Parameter TREATEMPTYREPEATINGFIELDASNULL = 0;
    XData DTL [ XMLNamespace = "http://www.intersystems.com/dtl" ]
    {
        <transform sourceClass='EnsLib.HL7.Message' targetClass='EnsLib.HL7.Message' create='new' language='objectscript' >
            <assign value='source' property='target' action='set' />
            <assign value='"test"' property='target.{MSH-4}' action='set' />
        </transform>
    }

}

For the more visual people:

 But when I test this with any HL7 message I get the error

ERROR <Ens>ErrGeneral: Cannot recognize path before DocType is set

Is there not a way to write a DTL for any HL7 message without specifying the DocType? And also, am I referencing the field correctly with target.{MSH-4}? I want to use the segment name and position instead of the field name since I'm not using a DocType.

Hey Developers,

Play the new video on InterSystems Developers YouTube:

⏯ Chatbots are all the RAGe: Generative AI with InterSystems IRIS @ Global Summit 2024

Discover the capabilities of InterSystems IRIS Vector Search, including integrating dense vector storage and search with InterSystems IRIS SQL for advanced semantic search and other GenAI application patterns. This video will illustrate how Vector Search powers Retrieval-Augmented Generation (RAG) for chatbots, presenting practical use cases that transform your data and applications with AI innovations.  

Presenters:
🗣 @Thomas Dyar, Product Manager, Machine Learning, InterSystems
🗣 @Alvin Ryanputra, Systems Developer, InterSystems  

Enjoy watching, and get ready for more videos! 👍