Concatenate string values in a lower-level data frame

Not recommended to be called by most users; addFieldForeign with concatenateAll suffices for most purposes.

Usage

concatStringFields(
  simpleDF,
  complexDF,
  complexNodeMap,
  fieldnames,
  tokenListName = "tokenList",
  separator = "",
  ...
)

simpleDF: The lower-level dataframe, for example the token dataframe for chunks and units, or the unit dataframe for stacks.
complexDF: The dataframe that you're trying to add the concatenated fields to.
complexNodeMap: The node map corresponding to the simpleDF.
fieldnames: The fields to be concatenated.
separator: The character by which words will be separated.
...: Additional fields 'simpleDFAddress', 'complexNodeMapAddress', 'fieldaccess' (foreign by default) from lowerToHigher(). Only needed if you want automatically generated update functions.

complexDF