Text Processing Nodes Accepting Only DocumentCells

Dear Forumers,

I have a question regarding text processing nodes. I want to used them from a table kind of resources that I gained before. I would like to convert a String cell to DocumentCells as it is stated in one of the node help bubbles. This is eg. the Case Converter node, but I cannot convert my data type into DocumentCells.

Can you provide information how this data type gets created?


You can start with the following node to convert StringCells to DocumentCells: