The dictionary class is defunct as of rlang 0.2.0. It was
trying to be too general and did not prove useful. Please use
as_data_pronoun() or your own pronoun class instead.
as_dictionary(x, lookup_msg = NULL, read_only = FALSE) is_dictionary(x)
An object for which you want to find associated data.
An error message when your data source is accessed inappropriately (by position rather than name).
Whether users can replace elements of the dictionary.