Confusion about return types of retrievers

[wxywb]

when we set a rm in dspy, and we call the dspy.Retrieve, the following lines will be executed https://github.com/stanfordnlp/dspy/blob/b05394bb20722444648a33b4447156bcef202fd6/dsp/primitives/search.py#L8-L24 so we can see in L12, the passages return by retrievers should be a list of dotdict which has long_text attribute.

But we can find the base class of retrievers should return Prediction https://github.com/stanfordnlp/dspy/blob/b05394bb20722444648a33b4447156bcef202fd6/dspy/retrieve/retrieve.py#L32-L32

the official example which uses dspy.ColBERTv2 returns List[dotdict] instead of Prediction (although it is not a dspy.Retrieve) https://github.com/stanfordnlp/dspy/blob/b05394bb20722444648a33b4447156bcef202fd6/dsp/modules/colbertv2.py#L35

and we now have two kinds of retrievers, one return List[dotdict]

• azureaisearch_rm.py
• chromadb_rm.py
• clarifai_rm.py
• vectara_rm.py

another one return dspy.Prediction

• databricks_rm.py
• mongodb_atlas_rm.py
• pinecone_rm.py
• ragatouille_rm.py